2.2 When They Interfere over 1NTA jump to 4♦ or 4♥ is a transfer to 4 of a major (diamonds to hearts; hearts to spades).
Opener has no choice but to transfer as asked. Responder has either a hand with just enough to scrape out a game bid, or a hand he wants to bid RKCB after setting the trump suit. Stay out of the way.
| West | North | East | South | |
|---|---|---|---|---|
| 1NT | Pass | 4♥ | Transfer to spades showing 6+ | |
| Pass | 4♠ | Pass | 4NT | RKCB |
whereas the following is quantitative (invitational):
| West | North | East | South | |
|---|---|---|---|---|
| 1NT | Pass | 2♥ | Transfer to spades showing 5+ | |
| Pass | 2♠ | Pass | 4NT | Invitational; not RKCB |
When a Jacoby Transfer is used, followed by a raise to game (only the one auction shown), the hand is slam-invitational (otherwise a Texas Transfer would have been used):
| West | North | East | South | |
|---|---|---|---|---|
| 1NT | Pass | 2♦ | Transfer to hearts showing 5+ | |
| Pass | 2♥ | Pass | 4♥ | Slam invitational (hence 6+ hearts) |
| 5-5 in the Majors |
2.2 When They Interfere over 1NT |