Many years ago in the pre-internet era, I remember reading about someone in Ft Lauderdale who had grafted nine different varieties of mango onto one tree, so that he had mangos for almost 6 months a year from it.

It seems like such a good idea (I'd much rather have a few mangos at a time for a long period rather than 300 lbs all at once), but I've never seen anyone who sells anything like this commercially, so what are the downsides? I see youtube videos about people in India with preposterous numbers of grafts on one tree, but nothing at all in this country.

I figure there's got to be a reason. What would it be?