Agree about being just a bit slow. Just to clear up, Vini does take five steps,
so instead of 1..2..3..4..slide
try 1..2..3.4..slide. The 4th step is a quickie step.
When I decided that the free swing was for me, and abandoned the plant-n-pull, this is one of the big keys that I found to keeping the swing free and loose. Every now and then, I will forget about the quickie step, and this causes me to control the ball on the downswing just enough to lose the good release, and I usually end up pulling it. In my mind, I see the quickie step as a way of getting myself out of the way of the ball as it's falling down in the swing. In other words, let the swing do it's thing, and adjust the steps to let that happen. Before, my steps were what they were, and I would adjust my armswing to them.. if that makes any sense?
Having said that, it doesn't appear that you are controlling the ball on the way down... seems very fluid. So, I don't know, you could experiment with the quickie step... you may find that you are indeed controlling the swing just a bit on the way down.... if that is the case, by trying the quickie step, you may get yourself a couple more free mph's of ball speed.