Some random questions need answers

I wonder if you guys could help me answer a few questions i have to clarify my understanding of things OC related.

1. Does heat cause CPU errors from over clocking, i.e. Will a CPU that is unstable at a specific speed / voltage still be unstable if cooler at the same settings.

2. Is it better to have a faster CPU speed, say 4.5ghz and a lower FSB speed or a more balanced OC of FSB + CPU but at a lower overall CPU clock say, 4.2. I find I run hotter with FSB OC as opposed to multiplier OC.

3. Will stability increase over time, does the hardware get more used to the strain? Or is the opposite true,

4. Is going over the intel spec of 1.36vcore for my CPU a bad thing? I have temperature well under control at the moment

That's it for now. Just some general things I am not 100% sure of and would like to clear up in my mind. Ty ty Ty in advance

Yes heat can cause the CPU to be unstable . And yes it could also be unstable if it is cooler at the same speed as it may have hit the wall . This is to say that the CPU can only go so fast at any given FSB speed and voltage . Most CPU's are locked and this would give the CPU a limit to the Multiplier this is why most over clock with the FSB and as I have always had a Locked CPU I find mine are just as fast with a FSB over clock . But a 4.5GHz over clock with a multiplier is going to be fast than one with a FSB over clock of 4.2 . or vice verse .
You can go over the rated voltage on the CPU as long as you do not get too crazy like never go over 1.5 on the Vcore with air cooling or water cooling unless you just do it for a very short time and the temps do not exceed 85c . I could be wrong and often times I am but I hope I cleared some things up for you .