I don't know what problem occurs if rebid 2♠ only shows 5cd ♠.
opener could rebid 3♠ after 2N to show 6cd ♠, if opener holds 6♠ 4♣,he can choose response 3♣ over 2N and then bid ♠ again if possible.
for this ...
Do u mean if we have strong hand 1-suiter,we can only overcall(because X means two place to play)
Strong hand when they opening is not rare,since nowadays opening are lighter than before.
Aren't you afraid of losing many games?
I don't know why you claim of that.
what's the downside of dividing weak hand/mixed raise hand?
if we want to compete earlier,then 1D (X) 3♣(mixed)/3♦(weak) can both cause effect(disturbing opponents) and dealing opener hand well if he has strong ...
I have heard some pairs play 3m as mini-splinter to reach good game if opener don't have wasted value on it.
Is it worth to use it instead of bergen?
(Maybe the only downside is that they could find sacrifice.)