I was chatting with a buddy of mine about replacing my windows and I
mentioned that I was planning on removing the siding to get to the window.
He basically shook his head and mentioned that typically what is done is a
circular saw is run around the perimeter of the window and that is what is
used to remove the window. Basically he described it as cutting out the
siding that hides the window frame and attachpoints then installing the new
window, then using 1x2's or whatever to frame the window and cover up the
cut the circular saw made.

Is he basically correct here. For some reason I just can't see myself
taking a circular saw to the siding as proper window replacement.