The "triofusion" strategy was exposed by Gauher Chaudhry during his PayPerClick Formula 2 course. It is one of the methods to expand your keyword list. It is based on the concept of "connected keywords". Here you would take your well performing long tail keyword phrases (3 words, "trio") and enter them into the input form. The program will "fuse" and permutate the words into new key phrases that you can add to the keywordlist of your PPC campaign.