He does have an S4, maybe he should invest in some turntables.
Unfortunately a lot of new people who jump in and just learn in the digital age, don't have the joy and frustration that comes with true old school djing, and beat matching. Nothing ever stayed locked for long, it's always a constant battle making sure everything was always staying in time.
I think a sync button just takes the fun away from learning true Djing, yes tons of people use it, and I'm sure for some stuff it's nice to have especially if you use remix decks or are midi clocking with a program like Ableton.
The S4 is probably a great tool, heck I'm getting one for Xmas, but as many of the other people posting head the advice, try not focusing on whats going on with the software, learn not to start out using tons of Effects back then it was how you Eqed, volume and crossfader cut your tracks, all those things that really made your set stand out.
Learn to count beats that was the first thing I did I can count a beat to any song, I may not know the tempo, but I always know the beat and programed my brain to learn when all the changes happened.