Vampyr, on 2013-September-15, 09:36, said:
The problem is that partner will bid as though I have five. I don't want to be getting too high and going off in 3♠ or 4♠ if they can't make 3♥. A response structure that caters for partner overcalling with four isn't normal in the Acol environment in which the original question was set. Maybe other envronments have different response structures? Last time I looked at the vote, none of the 1♠ bidders were Acol players.
This is the N/B forum. I think answers should assume that partner is intermediate at most, and keep it rigorous.