Since Finesse-It probably has a grit in it (it has some type of abrasive, I believe), it basically rubbed off the Black Magis which I know does not have any grit in it. Thus you were probably left with only what the Finesse-it did. I am not a chemist, but this makes sense to me.
Using the Finesse-it should, depending on how much effort you put into it, do all the normal things: make it skid longer, make it hook more in the back end, and make it handle less oil. The harder and longer you press, the greater the effect. Of course, it will only hook so much in the backend and you're not increasing the hook, only moving it to the backend.
So far, for me, the only products that reduce the backend are auto polishes (ones with wax), Neo-Tac's Control-It, and VERY HEAVY applications of Black Magic. I no longer ever use car waxes on balls.I use Control-It intentionally and I mark such balls carefully, as only sanding removes Control-It. I am very careful how I apply Black Magic, depending on how much skid I want. It is easily and WONDERFULLY controllable. If I want just a little, I do it by hand, without the spinner. Great Stuff. (been using it well lately; sorry if I went a little overboard. It is good stuff.)
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