Not sure I would define myself as a strong player, but ... I'll dare to comment anyway.
First, your observation is interesting and matches my anecdotal observations regarding typical amateur chess player foibles: we tend to miss real threats more often (or to a greater impact) than we overestimate them.
2nd, - to your post's query more directly - my thought was that a greater understanding of the plans and strategies peculiar to the opening being played would lessen the likelihood of attending to issues that were not of high importance (assuming the tactical implications were not serious, only the strategic ones). I believe this is one of the greatest weaknesses in amateur play: having a less-than-adequate understanding of the ideas and themes for both players in the openings we play.
Just my few thoughts on your excellent question.
Hi everyone. I've diagnosed a rather odd weakness in my game and I'm looking for help in trying to overcome it. It has plagued me in a number of my recent OTB contests.
I seem to overestimate the opponent's supposed threats and take defensive measures where there are none needed. Last night, for instance, I committed most of my forces to defending a pawn that really wasn't very important. A post-mortem of the game with one of our club's strongest players showed that had I instead activated my pieces and let the pawn fall, I would have had a good game and it is likely that my opponent would never have taken the pawn anyway, because it was simply a distraction from their real plan. By committing all my energy to the defense of this phantom threat against my pawn, I gave the opponent opportunities to create real threats elsewhere on the board, and those threats did me in.
What causes this bizarre weakness? I know a lot of players who fail to perceive real threats that their opponent is working up, but I don't personally know anyone else who has this very opposite problem like I do.
Any strong players out there have some advice on how to strengthen this part of my game?