This could be a life long project for science and the bud smokers of the future. I feel like a scientest sometimes. But both methods im going to try. My uncle splice grapefruit and lemons this way.(by graphting) There's alwayse problems though. Special care i.e. Feeding the main plant different nutes, maybe using a clonex solution for better fusion of the stems. Only vigorous strains should be used. And Probably need fat ass stems on the bud, like 1/2 inch maybe