I do believe that there's more to it than that if you want to make hybrids...
To stop self pollination, people often cover the stigma and cut of the flowers own pollen spikes...
On top of that, there is the part where you said you grafted "onto a seedling", where as the part thats used as a host with roots is called a grafting stock. A seedling is a young plant, where as grafting stocks are often older columnar plants with high growth speed and tough roots..The part you graft on the stock is called a scion...and IT is either a seedling, an offshoot/branch, or an areole in rare cases...
