forcing or not

1♦ - (2♥) - DBL - (pass)
2♠

this is a joke, of course. but i had once a partner who was convinced 2♠ is a reverse bid. it is not! double promissed (or at least suggested) spades, so opener is in fact just giving fit in a suit announced by responder.

1♦ - (2♣) - DBL - (pass)
3♥

this is not quite a joke. after a negative double on 2 level, jump by opener can be treated as GF (proposed by Wolf i think). the reason is that the pair has at minimum (15)16 HCP + (7)8 HCP. this will make the cue-bid less overloaded in this position