How is it a constraint? Is it a constraint in the P07/P09? I guess I don't get the point.
Every design requirement is a constraint. If there's a benefit tothe requirement, you might call it a feature. But if there's no real benefit to it, then it's nothing more than a constraint.
My understanding is the CZ slide-in-frame design is to lower the bore axis.
I've heard that. I've also heard it makes them more accurate. I suspect both are brand myths.
Rather than derail the thread with gun design theory, the few different ways you can lower bore axis, and how slide-in/slide-out need not affect any of them, I'll just suggest that going the design path of the Glock, which has an exceedingly low bore axis, is probably a pretty good path to a low bore axis.