[Shovah32]

Imprisoned pretenders can be used, but you need a very strong early and mid game if you want to make use of them generally.
A combat pretender who is imprisoned probably wont appear until there are alot of SC counters around - and of course wont be able to defend against rushes.
An imprisoned mage pretender intended to diversify magic will often be a little too late to have the sort of impact you would really want on your versatility.