There are ten cars in front of you.

And someone is asking which one is the fastest.

Then you look at each one and say "that one".

But the fastest car you found is the fastest car among the ones in front of you.

There are other fastest cars around.

Now, "fastest" changes from one perspective to another.

The fastest for you may be the slowest for me.

Take Skimask's example:
LOOP: For I=10 TO 1 STEP -1:NEXT I:GOTO LOOP

if you run this with 4mhz, you get the "fastest" loop.

If you run the same loop at 20Mhz, you get the "fastest", too, but faster then
4mhz.

If you run it at 40Mhz, you still get "fastest" but faster then 20Mhz.

Now, you do the math.

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