Posted 2023-June-02, 23:50
The problem is that you took the robot "out of book". This kind of auction isn't really supposed to exist, because hands with spade support are either supposed to raise immediately over the double (with 4 cd support, to 2S/3S/4S, or make a splinter, or bid 4c with a 4/6+ type of hand), or redouble (support, 3 cd spades exactly). So this sort of delayed, deny support initially, then show it later is not really supposed to ever happen, so it falls back to some default rule that it must be 3cd support, but North has no idea how strong it is (see explanation, up to 17 total points) because this sequence isn't programmed into the normal bidding book, because South was supposed to raise to 2 right away, which would show a minimum opener with support. There's no "pass then raise later to show that I opened a bit lighter then minimum on something that maybe shouldn't be opened". If you just raised immediately over the double, this probably limits your hand more and North maybe doesn't bid so much.
Also maybe things like game tries with the North hand aren't really defined on this sequence, so it feels no options than just blasting game.