Easy to explain. The Dems can't use their stolen punch card voting machines to double punch GOP ballots thus spoiling them. It would be interesting to find out the spoiled ballot rate for 200 and 2004.
Well since there were only two choices for a Florida county (touch screen or optical scanners) all punch card spoiled ballots were eliminated.
Most counties that already had optical scanners chose to keep them, counties with punchcards could go to the touchscreens or optical scanners.
You can't spoil a ballot on a touchscreen, they alert you a zillion times if you've undervoted (I know, I chose to not vote on a race in our county elections), and it's impossible to overvote.
Optical scanning machines, during the 2000 recount proved to be the most reliable in the state in duplicating the same numbers during a recount.