6291..less invalids which I'm too lazy to query a count of.
Uhh no you did not mine 6291 blocks. Your users mined 6291 blocks.
Let's get that straight.

The coins go to my wallet, I just give them an IOU

. I've just been nice enough to honor those IOUs.
While effectively doing a 51% attack and invalidating everyone else blocks. Curious did you do this out of malice towards the new blockchain (which your message about it being a ponzia scheme seems to indicate you think is a bad thing to have), ignorance, just did not care, or you wanted to show the effects as an experiment?