I have never heard of any method which uses 3♥ NF. So after the opponents bid at the three-level you have no way of playing anything other than game - even a takeout double would force to game as partner can't be guaranteed to have a suit that he could bid at the three-level. With ♠ KJ10xxx ♥ xxx ♦ xxx ♣ x knowing that our side likely has the balance of strength I have a choice passing or forcing to game. Meanwhile if I want to be in game I have multiple ways to get there - forcing 3♠, jump to 4♠, Double then bid etc. It makes little sense to me to not have some way of competing for a part-score when the hand belongs to our side. Some people transfer here, which I think is a fine method. I said I have never heard of anyone playing 3♥ NF, not that I have never heard of anyone being able to play 3M. Also I disagree that double is forcing to game.