Yes....it would be very dangerous indeed to use a complex logic part beyond the specification ranges that it is specified for. Just imagine what could happen in the case of a microcontroller running at 24 mHz instead of its specified 20 mHz. Everything could appear to work until you came to the, for example, the DIV AB instruction which may be the only instruction to use a tiny piece of logic in the corner of the chip that does not work at the 24 mHz. Even more devious would be that the DIV AB failed to work if just the sign bit of B register was set!!

Just remember my story. Did that silly basic program exercise every aspect of that 8080 S100 system and verify that it ran correctly at 3.7 mHz.......Of course not!

Michael Karas