Don't know if this can be of any help, maybe Paul or other real coaches on the forum can judge.
Don't bother too much Jonathan. This is not the olympics, I always tell myself. Makes me play more relaxed. But now seriously:
I always try to analyse my game. Not easy when you're on a tournament, I know. The tension and stress it brings… But I think this is vital, for answering the change of tactics of your opponent(s). In my former days, this analysis came after the match, too late. Don't know where the click came from, but I play more relaxed lately, and now I'm able to analyse my game troughout the match. So when I do things that don't work, I change after a few mistakes, I then go for the rally's and try to outplay my opponent(s). I'm no coach, but these 3 simple questions (but more important the answers to them) seem to work for me:
1) where did I lost most of the points, and what can I do about it
2) where did I win most of the points, and why shouldn't I exploit this to the bone
3) what is my opponent(s) aiming for ? Did he discouver my weakness(es) ?
First question, I try to avoid getting myself into trouble, highly related to the 3rd question. Suppose your backhand is rather weak, avoid using it. Take it forehand, or “roud the head”. Avoid your opponent(s) can use his/their best weapon.
Second question, don't take risks. If I was on the winning hand, I tended to try things, especially in MD. I stopped doing so. Clinch the match and save “trying things” for the club meetings. If I'm on the loosing end, I go for rally's halfway the game and try to even the score.
Third question, avoid to show your opponent(s) you weakness(es).
Once I played in a meeting for ranked players (I'm not ranked). I played mix, but my partner was higher ranked than me. We played XD like MD. We won eyes closed, 2 straith games. Why, because we did a brief analysis of our opponents before the match, and because my partner was able to hit power smashes, or a descent clear.
All of this is so much easier when you're at the sideline watching somebody else playing. But when it's you on court, there're so many things to think about. And on some occasions, you just simply have to admit the other side of the net was better… You win some, you loose some. But the possitive thinking strategy Paul mentioned on a forum item, is invaluable if you ask me.
So cheer up, and prepare for your next meeting/tournament/… On the WC2005 Lin Dan got humiliated by Taufik in the final. Look what became of this Chinese superman, he won all there is to win in world badminton.

Well, maybe to keep things realistic and to not always bring the good news show to this forum: I had a lesson lately. I played singles, played relaxed, and rather focused. The opposition was something like 20 years younger than me, but of equal ranking. All through the match he smashed something like 5-10 times. Not much you see. I tried everything that I've been trying the last couple of months and that worked fine. Well this time, all the shuttles kept on comming back.

Brief analysis: not that I made a lot of errors (real errors like in the net, out, …), a few of my netdrops were not sharp enough so he reached them in time so he could drive them back behind me. His smash was maybe less powerfull than mine, he was just in all circumstances far more efficient and quicker than me. So about the entire match he outmanouvered me. There's no doubt in my mind this guy will walk through the lower ranks of competition quickly, and settle somewhere between the higher ranked players.
There's was nothing I had in my abbilities that could distress this guy. That's the time I know I simply have to congratulate him with his performence. I won't give the results, just take it from me: he won . But that's not going to keep me away from what I like to do. As mentioned before, you win some you loose some. Now it's time to lick my wounds, and prepare for the next match.

Cheers, ED