Playing with Harry we had a poor score North / South, but there wasn't a lot we could have done about it. However:
My RHO opens 3NT (long running minor) which is passed out. I hold:
♠ K 7 4
♥ K Q 9 8 5 4
♦ 8 5
♣ 6 2
What do I lead? Dummy should have a heart stop, so looks like Ace. I didn't think KH could be wrong, but oh boy! Dummy has 3 to the Jack, partner has doubleton Ace. Instead of down 2 it made plus 2.
On another board my LHO opens 1H, partner doubles and RHO bids 2H. I bid 3D and LHO bid 4H. PArtner hesitated for a while and passed and it came round to me. I hold:
♠ 9 8
♦ Q 7 6 5 4 3 2
♣ A 7 2
I acknowledged my partner's long pause but bid 5D anyway which I was intending to do before partner paused. Anyway our opponents found clubs before I could set up partner's spades for two discards and went 3 down undoubled, -300. Second bottom, a lot are in 5Dx but got rid of their clubs for 1 down (-200). Only 1 person was allowed to play in 4H which made.
Other than that we made just one obvious overbid (very constrained for us!) and misplayed one hand (well, only one definite misplay). I am afraid the rest was down to opponents who clearly find us an easy touch.