Agreed, but when you compare the difficulty of a dj set using Ableton to one on decks, you've effectively removed two of the hardest elements - beat matching and getting a track to drop on cue. I'm just an amateur tinkerer at best, but those two elements are the hardest parts for me to get right on tables. Ableton matches the beats and, if you know your tracks, getting them to drop at the appropriate time is so easy a first grader could do it.
With Ableton, you've still got to learn the software and know your tracks, but a lot of the technical aspects of spinning are completely handled for you. Anyway, my point was that without those two elements, you're left with finding two tracks that sound good together and mixing them properly so that they don't overwhelm one another. The skills required have been halved. Why someone would go the extra step of removing the last two difficult portions of mixing by doing the whole thing at home is beyond me. Ableton makes it significantly easier to simply mix two tracks together. I'm not knocking those who use hundreds of loops in a set and really push the software to a point that would be impossible using only turntables (Bas Mooy mention above). That IS impressive. What I'm asking is why anyone would pre-program an entire standard mix (one track to the next) at home when doing so on the fly with Ableton is so easy a plebeian like myself can do it?