I have never played those kind of 4-level transfers and I suppose that you have another way to transfer with a strong hand (FG) and ♥ (Rubensohl...) So those kind of transfers can be done with a weak hand and long ♥. Therefore, pass should not be forcing in any case ! By the way, for those who are playing Texas, what's the difference between 1NT 4♦ 4♥ and 1NT 2♦ 2♥ 4♥