MrAce, on 2017-July-13, 18:57, said:
Let me try again:
Suppose Advancer has
a) 2 hcp, 1633
b) 6 hcp, 1633.
He knows that partner can have e.g.
c) 19 hcp, 4243
d) 19 hcp, 5143,
so if the style is to respond 3♥ to the double on both a) and b), partner will not now what to do over that with c) or d), and also the partership may be too high already.
So even with the (standard expert) agreement that 3♥ is PRE, why not bid
* (1♣)-X-1♥; 1N-2♥; P with a) opposite c);
* (1♣)-X-1♥; 1♠-2♥1; P with a) opposite d)
and e.g.
* (1♣)-X-3♥; 4♥-P with b) opposite c);
* (1♣)-X-3♥; 3♠-3N; P with b) opposite d)
?
1 It's pointless to rebid 2♥ over
(1♣)-X-1♥; 1♠
on a 5-card suit, because there's no way a 5-3 H fit can be missed after
(1♣)-X-1♥; 1♠-1N/2♣.