It’s like a carpenter saying you can’t use an electric drill to make a hole in a wall. New gear gets introduced. Rejecting it makes no sense. You should use technology to make your life easier.
That said, we are strong advocates of being able to manually do things. Syncing depends on beat-gridding, beat-gridding depends on music style and software. The best software with the easiest music might get close to 100% accuracy, but more likely is between 65-80% accurate beat-grids. Then you can do some manual correcting to get the grid right.
Whatever you do, you will always be left with a percentage of tracks that can’t be beat-gridded correctly. Then there is matching tracks to other sources (CDJs, USB-sticks, other DJ’s laptop, etx.). Another thing where sync buttons don’t help. In all those cases you want to know how to do it manually.
So, I’ll second the notion that a DJ limited to only being able to do beat-matched transitions with sync has a severe disadvantage over DJs that CAN do it manually. I don’t say is or isn’t a real DJ or other things, because if you can only use sync, yet your music selection skills are such that you blow the roof of a place and rock the party, you are still a real DJ imho.
At the end of the day, beat-matching is technical skill that is way secondary to music selection. I would say use sync where you can as it will give you time to interact more with the crowd or explore other creative things to do, but make sure you can do it manually when the need arises.
Just my three cents as usual.
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