Blue Eagle - I am surprised. On a similar visit to LATCC the D+D controller told me to select sby first to avoid the setting off of the alarms for the usual codes, but also to avoid the 'others' which set off alarms which we as pilots are usually unaware of. (such as 0030 for 'London FIR lost', (I might have the number wrong)).
He said that if 7700 is recieved, it might be the last thing a pilot is able to do in an emergency, so they still call the services out. He said that it had happened and left them in a real dilemma.
I can see airmanship points on both sides of the arguments however.
Seems the answer is not at all clear and depends on the fit in your aircraft.