AIUI TrueCrypt has one hidden volume for every real volume, so it's reasonable for law enforcement to ask for the hidden volume if there's a real one. But what

AIUI TrueCrypt has one hidden volume for every real volume, so it's reasonable for law enforcement to ask for the hidden volume if there's a real one. But what if there was a hard disk encryption system that allowed a large number of hidden volumes (say 1000), and a suspect provided police with keys for 5 of them -- how would the police know that there was any more? I think that this would give more effective plausible deniability.