Jennbridge: Michaels and Leaping Michaels

A direct cue bid in a suit the opponents have opened is known as a Michaels cue bid.  If the opponents open one of  minor, a cue bid of 2 of that minor shows the majors; if they open one of a major, it shows the other major and one of the minors.  A jump cue bid, conversely, asks partner to bid 3NT with a stopper in the opener's suit.

When they open with a weak 2 bid, it gets more complicated.  Jenn and I, along with many pairs, use a convention sometimes called Leaping Michaels.  With a 2-suiter including the other major and a minor, we jump to 4 of the minor.  For example, if RHO opens 2H and I have 5 clubs and 5 spades I can jump to 4 clubs to show the 2-suiter.

So, having this agreement, what does a direct cue bid of 3 of their suit mean?  I confess that I had not discussed this with Jenn or any of my other partners.  Does it still show a 2-suiter, but perhaps weaker than a jump to 4 of a minor, or does it ask partner to bid 3NT with a stopper, just as if the opponents opened 1 of the major? 

I was playing on-line the other night.  RHO, non-vul vs vul, opened 2 Spades.  I held:

♠  K
♥  A8
♦  AKJT8753
♣  84


It looks like 3NT would have a good chance if partner had, say, Qxx of spades, as diamonds are likely to run.  If not, 5 Diamonds may be right if partner has something useful in hearts or clubs.  Since I was playing with a pick-up expert partner, I probably shouldn't have risked a 3 Spade cue bid, but I did, hoping partner would be familiar with Leaping Michaels and interpret this as asking for a spade stopper.  A more practical solution would be to just bid 5 Diamonds or 3NT and hope for the best. 

Unfortunately, LHO raised to 4 Spades and partner, holding

♠  A43
♥  K9764
♦  2
♣ QJT2

 bid 5 Hearts, which went down.  5 Diamonds or 5 NT would have made, and we'd even have done well doubling 4 Spades, which would have gone for -500.  He expected me to have hearts.  I asked him if he played Leaping Michaels and he did, but he said, correctly, that to expect him to work out that this wasn't showing hearts put too great a strain on a casual partnersship.  If you were playing with your regular partner, would you have gotten this right?

Good luck!