Posted 2013-October-28, 20:24
The question involves definition of terms. No matter whether 1NT is natural, semi-forcing (alert or announce), forcing (alert or announce) , or specifically demanding 2C (alertable), it is not a "psych control". The bid might be a psych, in that it grossly overstates values.....the tendency to do that should be disclosed as part of the alert if 1NT specifically requires a 2C bid.
But a psych control is a continuation bid which is wholly or in part designed to allow for the psych, not the psych itself. Gazzilli has no such properties, because it is only used after certain value opening bids. However, if opener rebids 2C with a hand inappropriate for the convention he could be using a CPU or fielding a psych and using 2C as a psych control.
So, the prohibitions on psychic controls do not apply to the 1NT response itself, judging that Opener must have the values for Gazzilli.
A related situation would be using transfers over 1MX:
1S (X) 1NT ---1NT alerted and explained as showing long clubs with zero to 12 HCP. This isn't even a psych if it actually has the zero-count with long clubs, and a 2C rebid is not a psych control.
"Bidding Spades to show spades can work well." (Kenberg)