Bidding after 1NT-X

I think one area that few partnerships have discussed in much detail is bidding after their side has doubled 1 Notrump for penalty--either the opening bid or an overcall. I believe that standard practice says that all subsequent doubles of runouts are for penalties, but usually the discussion ends there. What does a pass show on this auction:

1NT(1)-x-2h(2)-?

(1)-12-14

(2)-to play

Sometimes the right spot will be defending 2 Hearts undoubled, but that seems to be a pretty narrow area to shoot for. Some kind of structure involving forcing passes has to be the right idea. My favorite method involves forcing passes and value showing, optional-type doubles. So the passes are consistent with holding a penalty double of the bid suit, intending to pass partner's double if he produces one. Direct bids at the two-level show a smattering of values and are not forcing. Two Notrump is Lebensohl and 3-level suits are game-forcing. When responder (to the original penalty double, that is) has a bust or near-bust, he passes, bids the next step after the second double, and hopes to land on his feet somewhere. Passing and removing the double to a major at the 2-level (on an auction like 1NT-X-2c-p-p-X-p-?) shows values and a real suit but is not quite game-forcing. If the opps bid to the 3-level, forcing passes are off. I read about this system in Barry Rigal's "Precision in the 90s." I guess the most important thing is to have some kind of discussion as to what bids mean after doubling 1NT--anything is better than guessing.