Internal generated clock muxing

Thx you Brad for the fast answer, I read theese topic now.

In my last project I could use clk_mux maybe (I'll check it now), whereas in the past I cannot do it and the only solution was cutting the path cause it was a false one.

I cannot do it in all the desing it seems because quartus need to understand that the 2 signal that enter in the clock mux are clock signals (now I'm trying to set them as clock, previously I used a normal mux and I set its output as a clock signal) but I think I'll see the compilation results tomorrow (more than 1hour of compilation and in 10-15 mins I'll have to go out of office).

For the idea to switch to Timequest I'll sure wanna do it but I need to do it when we'll start a new project (in which I wanna try also the top down approach with a full incremental compilation).