This entire thread is a load of shit. FFMpeg is one of the most intuitive pieces of software ever written, and has been deprecated for months. No idea why you're so hung up about there being an easy way to do things, the way you described is pretty hacky and takes more time and effort than just the normal ways, plus doesn't cater for weird formats or processes.
I don't understand why you think there is one tool that does everything, or why it's super difficult and requires godlike powers. I've yet to meet someone who makes amvs and actually knows what they're doing when it comes to video, I guess mirko and a few others come close though.