I think like many things here this comes down to what do you, as a golfer trying to improve, choose to do to advance that improvement. Will swinging at 'pro' tempo make you better or worse or have no effect.
The ams in my sample swing pretty much at pro tempo but not with pro swing results so swinging at pro tempo is not sufficient to produce a pro swing. This may seem an obvious conclusion but it is good to have some data.
It is also clear that matching a pro's time of downswing is not enough to produce pro distance. From some of the responses I think there were some thoughts that ams had 'slower' downswings and that was part of the cause for less distance. Again it's good to have some data.
So in each golfer's consideration of whether they should focus on swinging quickly or correctly (given that a focus on correctly likely means less quick), here is some data to help make an informed decision.
BTW - This exercise has caused me to rethink some of my opinions. I thought pros tempo was generally slower than ams. That was incorrect. They are often about the same. As I mentioned to petearm I think the perception comes because pros are not 'rushed'. They go at a speed that allows them to do everything correctly. When ams go at that speed they do not have enough time to do everything correctly so they are 'rushed'. That may be why petearm's champion am was noted as going slower. They succeeded because they went slow enough to swing correctly.