Well, Rob got me thinking. Then, seeing the spacing Chris has in some of her trees at Truly Tropical (
https://youtu.be/__Ne91TFnAc), I am more firmly considering just doing 8 foot spacing, instead of 2 in 1 hole.
Brogdon avo (already there)
8ft
Venus mango (to be planted)
8ft
Pickering mango (to be planted)
8ft
Unknown avo (already there)
I wouldn't be doing anything with the "extra" space the 2 in 1 planting would create, as it wouldn't really be that much more, maybe 11 feet from the avos instead of 8. Plus the 8 ft spacing will help more with disease and provide a little more wind protection in my gusty area.