West will of course will Pass and North has one of those awkward 4441 shape
hands. In Acol the classical opening is the “suit below the singleton”. If
North opens 1H South has a choice of actions. His aim should be to show a good
hand in support of Hearts; a raise to 3H would not be unreasonable as in Acol
this shows 10-11 high card points and four card support. Some Souths may think
that their shape needs more aggressive action and may bid 4H directly. (More
advanced bidders may try a “splinter” bid of 4D, this shows 10-12 high card
points, four card trump support and a singleton in the bid suit).
Whatever South does North is unlikely to be encouraged to go beyond game.
Although the computer says 6H can be made, in practice North has some choices
in the play and depending how many he gets right will make 10, 11 or 12 tricks.
Another approach is that given in the bidding. When North rebids 4H, an astute
South will deduce partner has at least 9 cards in clubs and hearts, or a very
good hand. With such lovely support in both suits, this may be a prompt to make
a slam try by asking for aces.