I know some people have agreements (at least over on this side of the Atlantic) that include forcing passes & takeout doubles in specific situations, but I think the normal thing in these sorts of auctions, without any specific agreement, is that double is penalty and you can (forcing) pass with any hand that might have made a takeout double. Passing & pulling shows a stronger hand (ie invites slam) than does making the same bid immediately. So when partner passed 4H he either said he didn't mind defending if I want to (which I don't see that I do), or that he wants to invite slam even if I do want to defend. I agree it's hard to construct hands so that everything makes sense, but perhaps the 4H bidder might have had nine solid missing the ace, and partner x, A, KQJ, AKQJxxxx (move a few small minor cards around as you wish). Now we're cold for a grand in three denominations [edit: actually only two] and 4H is only two off.