"Shields weakening/collapsing" is to establish why the ship gets a hole punched through it, but even if you cut those lines out the scene would still make sense.
The other example...you'd think it would be SOP to turn the strongest shield towards an attacker. It's as obvious as "don't turn your back on them" and, again, superfluous. I don't recall the context of the action you cite (I saw Nemesis
precisely once and will never watch it again), but assuming the enemy ship was still cloaked, I'd have written something like—and this is just off the top of my head, "Keep turning to keep the strongest shield towards the direction of fire. If he's like me, he'll recognize what we're doing and try to come around to the weaker side. That's what I'm counting on." And make it so he's trying to trick his invisible adversary from attacking from ANY direction to a more specific direction where he could let loose with everything he's got and have a better chance of a hit, which would show Picard thinking
and trying to outsmart his adversary, which would tell us something about the character and how he's using his knowledge of himself to outsmart his duplicate. One is reactive and rote, the other is smart and character-specific.