On a sidelock the lockplate itself contains the lockworks, and when you remove the sideplate, you have in your hand all the lockwork, attached to the sideplate. On a "false-sidelock" the works are in the action, the sideplate is merely a cover.
Greg, I don't know where you got this description, but what about T&S design, it's sidelock. BECAUSE, when you remove plates you can easily remove all lockworks after that. Its didn't attached to plates, but two axles of lockworks go through the plates.
The only difference by your words attached or not attached and I think it's insignificant in this particular case.
T&S's lockworks are the most simple design I ever saw. I used this gun for more than 2 years and I have to say it's very safe design.
