Your google fu is weak: http://tvtropes.org/pmwiki/pmwiki.php/Main/ScottyTime It even has a trope named after it. Not that I need examples to prove Scotty's practice. 'Relics' fully establishes it.
The only example on that TVTropes page allegedly from TOS that I see is from The Naked Time, only they got it wrong there. In fact, in that case, Spock figured out how to shorten the time, not Scotty, and Scotty's estimate on how long it would take to restart the engines was for real, for all he knew. Spock knew something Scotty didn't. So, sorry, it's you who have failed to provide any examples in TOS. The TWOK example is deliberate code, so that doesn't count. The STV example lampoons the trope, but without Scotty having inflated his estimate. For shits and giggles here's the scene from Relics, according to http://www.chakoteya.net/NextGen/230.htm: [As I said, it was Spock, not Scotty, in The Naked Time, who figured out how to restart the engines faster. Scotty and Spock worked together to do it faster than Scotty would have known how to do it on his own. For whatever reason, Scotty kinda leaves that part out here.] Point to me where Scotty advises La Forge to pad his time estimates. While Scotty's evidently surprised that La Forge hasn't learned to gauge when the captain needs something right away or whether it can wait, we never get to hear what Scotty's actual advice to La Forge is, because he cuts Scotty off. It seems to me that the whole point here is to make sure that the captain knows not to cut the margins so close that nothing can save the ship. Scotty's trying to keep estimates conservative to protect the ship, not his reputation. It was couched in humor. And anyway, Scotty never did this in TOS anyway, not that I know of. I'm eager to see whether anyone can produce an actual example.
Geordi. He was a no-bullshit professional and a nice guy who worked well as a character without this emotional working class guy charisma of the other four chief engineers. When he had to take command of the ship he also did far better than Scotty or Tucker (I don't think that O'Brien or Torres were ever at the helm).
O'Brien was first seen as the Ent-D's helmsman iirc he was just called "conn" He's also been seen at the helm of the Defiant.
We saw Scotty in command of the Enterprise on numerous occasions. I think on the evidence we say he would have made a good Starship Captain.
Like Tucker he lacked diplomatic skills and the vibe has always been that these guys feel more comfortable when they are down in engineering.
CorporalCaptain LaForge: I told the captain I'd have it done in an hour. Scotty: How long will it really take you? LaForge: An hour! Scotty: [flabbergasted] You dinnae tell him how long it would really take?!! LaForge: Of course I did. Scotty: Oh, laddie, you've got a lot to learn if you want people to think of you as a miracle worker. Now listen It's clear from the scene Scotty used to deliberately lie to his superior officers about the time needed to complete a task - a practice he considers desirable, in order to look good. It's also clear Scotty was about to counsel Geordi to do the same in order to make people think of him as a "miracle worker'. All you have is euphemisms and semantic irrelevancies. And fan-wank explanations for 'The naked time'. And you think these constitute an argument. Cute.
That conversation between Scott and LaForge is just a continuation of the joke from TSFS between Scott and Kirk.
O'Brien's official title aboard Deep Space Nine was "Chief of Operations," which is essentially the same as "chief engineer" of a starship, given a different title presumably because you can't have an engineer without engines, which a station doesn't have. I'm not sure if it's ever officially established in dialogue or not, but I'm pretty sure that once the Defiant was introduced, O'Brien was Chief Engineer of that ship as well. He was certainly in charge of engineering. There wasn't anyone else in evidence who could be filling the post. And it would be odd of they called him "Chief of Operations" when literally every other Starfleet vessel we've ever seen has a post named "Chief Engineer." Regarding the OP's question, I think my vote would go toward O'Brien, with LaForge being a close second. O'Brien seemed to have an immense amount of technical skill and was also one of the most well-developed and well-rounded characters in all of Trek. And, I'm sorry, I love the TOS crew including Scotty. But if we are to go by actual on-screen evidence, Scotty was not the miracle worker he's made out to be. More often than not, when Scotty performed an engineering miracle, Spock was there making it possible. Whether it was doing a cold restart of the engines in "The Naked Time," cross circuiting to B in "Obsession," or fixing the engine imbalance in TMP, Spock was more often than not the one providing the real solution to the problem.
^From a technical point of view it does, as an engine provides the power. A modern example would be a car enginge which burns a fuel which provides energy which is turned into a mecahnical motion. In ST inside of say diesel it uses Matter and Anti-Matter to provide energy. The station has a power core which provides energy.
I gotta go with the brogue. Scotty. There is no comparison. He has no equal. And he's givin' it all he's got, Cap'n!
Psst...LaForge can modulate ANYTHING into whatever he wants. I love it when he's trying to figure out a problem and starts questioning the computer, narrowing down solutions/problems. Such an underrated genius. He leaves all else in the dust.
^ LaForge is an excellent engineer, but I think O'Brien is the better character. Which is why I picked O'Brien.
the Asian guy from "the Naked Now." But if we're going by regulars, I'd say Geordi LaForge. Scotty was good but he was rarely IN engineering in TOS, he was usually on the bridge taking over for Kirk. Plus Geordi had the cool VISOR.
To quote a previous poster: "I want to say Scotty, but I keep remembering his insistence that it takes 30 minutes to restart the warp drive in "The Naked Now" ("I can't change the laws of physics.... I've got to have 30 minutes!") vs. Trip doing the same thing in "Divergence" in 2 minutes ("That's impossible!", "Watch me!")" I couldnt agree more. Trip was the engineer of the first warp 5 ship. he wrote the book. Scotty( in all his brilliance) just read it . Scotty had the benefit of having almost 100 years of humans experience with flying god knows where around the Alpha Quardant, while tinkering with Warp 5,6,7,8,and 9 ships before him. Not to mention whatever knowledge the Vulcans ,Andorians , and Tellerittes gave to the Humans as part of the mutual contributions after the Federation was created. Tpol called what Trip did "impossible:" Even though she wasnt an engineer its still Very high praise coming from her.This is from a Vulcan who part of a species that possessed warp drive centuries before humans did and all without anyones help( except for that engineer from the episode Cogenitor.) Still Scotty kept himself alive for 75 by rigging a transporter.... Something Laforge called "a genius" Honestly want to give it a a close tie between Trip+ Scotty,but if had to choose as much as i bow to Scottys brilliance, Trip gets extra points for being older and not being a starfleet grad, and not having anyone come before him like Scotty did. Scott did say it takes 30 min to restart a warp drive.. Trip outdid him there. Plus Scott lives alot longer, in fact as far as the canon goes, hes still alive BY the end of the TNG timeline in Nemesis.Trip did all that and he was in his mid 30s before he died young. the only thing that puts Scotty almong the best was his transporter lifeboat idea, but for all we know Trip might have come up with the same idea( to survive in a pattern buffer) I certainly wouldnt put it past Trip. Trip had NO ONE come before him and he still made his miracles. I bet if Trip had made it to Scottys age ,i have no doubt Trip would be twice the engineer Scotty was.
O'Brien. Really likeable "everyman" type of guy, I'd instantly want to buy him a pint if I met him. You can always rely on him getting you out of a tight spot. Plus the poor bloke has to suffer such a lot, so he gets my sympathy vote as well!
O'Brien. Sure, any human engineer can make Federation technology work but, only O'Brien could make Federation, Cardassian and Bajorn tech work together.