We play that the inverted raise is off when the opponents interfere. But because of our other methods, the jump raise remains preemptive. A new suit by responder in competition at the two-level is not forcing. A new suit at the one level is forcing.
The following sequence is not-forcing:
1m - (P) - 1M - (P)
1NT - (P) - 3om - (P)
?
Where m = a minor, M = a major, and om = the other minor. Responder is showing a weak hand with a three or four card major, and an expected 6-card minor suit.