Take these two recent matchpoint examples:
Case 1
Balanced 15-counts are dangerous for our 16+ 1♣ system. Most of the field made +150 or +400.
It's easy to say that East should bid 1NT but the hand looks suitable for 2♥. If partner has five ♥s, 2♥ rates to score better, or at least match the field.
If you play a method like ours, what are your guidelines for raising on three?
Case 2
Forget the North-South bidding. Can't argue with their success!
Those who opened 1♣ had no problems scoring +140 in 3♥.
West might have bid 3♥ first time, or had 2nd thoughts when 3♦ came round.
Hard for East to act, though favourable vulnerability at MPs makes it tempting.
Perhaps East can double to say "We were making 2♥, let's bid to 3♥ unless you have raised on three." Or should that double be a game try based on a 5-card heart suit?
At IMPs too, don't want to bring back "-140" "-110, 6 out."