For those wondering, Archer as Future Guy was always the idea.Trying to repair a corrupt future by influencing his innocent past self.
Go home Brannon Braga, you're drunk.
And specific highlights on what Season 5 could have brought
- Coto wanted to revisit the Mirror Universe on a regular basis with four or five episodes spread through the season as a "mini-series within a series." Mike Sussman and Coto had discussed places to go with it and it was "big regret" not getting chance
- The two main things they wanted to do with S5 was the "origins of the Federation" and the "begin whispers of the Romulan War", and tying those two together
- No other major villains were planned to be introduced, the Romulans were going to be the big villain, but would have new ones within new ‘mini-arcs’
- Rick and Brannon thought Future Guy was "probably going to be a Romulan" and would tie into the Romulan War with a future Romulan trying to "instigate" things
- They wanted to make Shran a regular character on the bridge of the NX-01 as an "auxiliary or an advisor…get Jeffrey [Combs] Somehow"
Obviously kept his indentity somewhat fluid then, and considered more than one option. Or simply heard some fan's deduction somewhere and with nothing ever committed to screen, thought it as cool an answer as any to say onstage.
It couldn't have been Archer, because a) he would have to have ended his days in the 29th Century... which I believe is the time worked out by Daniels in "Cold Front", as being where the Suliban's mysterious benefactor was from.
b) why would he be giving cloaking technology to an enemy intent on destroying Enterprise all the time anyway? To say nothing of Silik and his kind's genetic enhancements.
I've heard this theory before, but given what they established after "Broken Bow", I think you can safely rule Archer out.