From a basic gardening point of view this is only advised if you pull out the smaller one after they get going. :sadcrying

If you just leave them like one big plant the theory is they will compete and if one does not die off they will both never reach full potential. I say theory because I've seen plenty of pine trees and garden veggies do well. In your case I think you'd have to plan on more frequent pot changes and ending with a 5 gallon pot or probably even bigger. :yippee:

I'd vote: one per pot and one per hole. :thumbsup: