wank, on 2013-July-01, 15:20, said:
these questions have nothing to do with 4th suit [colour] forcing. 4th suit forcing is when your side has bid the other 3 suits naturally, then bids the 4th suit.
on hand 1 3c is normally played as not forcing. though it would be perfectly reasonable to play it as forcing. if you don't play support doubles, you can differentiate between the 2 types of 2c bid by doubling then bidding clubs later as opposed to bidding them directly. if so, it's normal to play doubling first as forcing and bidding them direct as non-forcing. if 3c is non-forcing for you, 4c is natural and forcing.
on hand 2, 2h is forcing as it's a reverse (i.e. respnder must goto the 3 level to give preference to your first suit). as 2H is forcing, it can be used for all the natural heart hands. 3H can therefore be saved for something different. a common choice would be a splinter in support of spades (with short hearts). whatever else you play, 4d is a splinter in support of spades (with short diamonds). as for 4H, following the same logic as before, it shouldn't show hearts. a popular choice would be exclusion keycard blackwood for spades (heart void).
I know, I know, "4th color forcing" here is different from "non-competitive 4th color forcing (to game)".
Well, if 2
♥ in question #2 is forcing because "responder must go to the 3 level to give preference to your first suit", the same is for question #1. The difference is, in board #1, opps bid and support the a suit (opps have a fit), while in #2, not clear if opps have a fit.