Please tell me about ignition timing

[novocaine]

Ok I've been talking to people and reading articles and I am completely confused now.

With regards to 20v

Its reccommended that a 20v timing be set to anything from 12 degrees to 16 degrees with the standard being 10.
So basically at 1000 rpm the timing would be 10 and in the higher revs the dizzy would advance it right? to a certain maximum value.
Now, is the advancing of the timing done to lessen the "time" from 1000 to whatever revs sees the timing advanced to the maximum amount?

Does that change the amount that the the distributor advances? if say the dizzy advances 30 degrees and the max value is set to 40, and we manually advance timing to 16 degrees does the max value change to 46? and is it because of that higher degree of timing at higher revs that there is an increase in performance?

OR

is an increase in performance perceived because the dizzy only has to now advance from 16 to 40 and it is saving time on the last 6 degrees?

Have i completely lost the damn plot?

What is the "advance curve"? is it a measure of something or is it a phenomenon?

This guy i was speaking to told me that its best to get the advanced curve to a smaller number, what i understood by advance curve is that it is the amount of degrees from lowest to max degrees? and he told me that the way to do that was to modify the distributor...................


ok i have a few more questions but i would really appreciate some clarification on these since they might nulify the next.