Service position on bat

Hi. I've heard and read several times that in order to get more spin you have to make the ball roll against the rubber for a longer distance, hence starting the contact point at the leading edge will give you a greater potential distance, compared to the trailing edge. But to me this is bogus, since when you look at the contact patch on the rubber (with a brand new ball and a freshly cleaned rubber you see it very well), even when you brush as much as possible, you'll barely make the mark look like an oval, instead of a circle. Certainly not a line. Hence the contact patch is like 1cm max on the rubber. Supposing that the reaction of the rubber/bat is the same on the whole surface, what matters to get spin is how fast the bat travels at the contact point, and how much the ball grabs into the rubber. So if you achieve the same speed and impact, it doesn't matter which part of the rubber you use. That being said, for shots with a limited movement amplitude, like a serve or a push over the table, it is very possible that if you hit the ball with the leading edge the bat will be traveling fast, and if you hit it at the same point in space but with the trailing edge, the bat may almost have stopped (to not hit the table, for a push over the table). The same should not apply to big swings like away from the table chops, where you finish the movement way further than the contact point. A counter-example is the top-spin : you also want maximum spin, but you're not targeting to hit the ball at the leading edge. Instead, you're aiming to use the top of the blade (if the handle is pointing down) because that is the point of the bat that is travelling the fastest.