I'm not sure that I've ever seen this sequence at the table. It featured in a quiz in Contract Bridge Journal in 1947 and I thought that it raised an interesting question of interpretation. Conditions were not stated but assume MP with neither side vulnerable. The opponents are playing four-card majors.
Jack Marx, who set the quiz, commented that 3♥ was natural since East could have bid 3♠ unambiguously if he wanted to force his partner to bid. This is fine so far as it goes but how strong should 3♥ be? It also occurred to me that one could use 3♥ to show values in hearts and invite partner to bid 3NT with a spade guard. Or even asking for help in hearts (i.e. implying values in spades).
All comments welcome!
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