Jim Macklin wrote:

But if an airplane
can roll to 60 degree bank it can be held in the roll and it
will become inverted and then because of the inertia
continue back to upright.

Not necessarily, and certainly not because of the inertia.

If you stop inverted you will
have problems because most engines will quit after a short
while, you might have some reduced aileron control and you
probably didn't hold forward elevator so you split S'd out
and roll control was returned.

Or more likely, if done accidentally ("didn't hold forward elevator"),
the airplane broke because of overload.

You should cease to spread dangerous wisdom about things you don't
understand. (As well as cease to top post.)

Stefan
(Removed PED, because this isn't.)