Scott there are many, many , many DJs out there that just push play! Many of them also reside on this board. Show me a DJ with a single out Soundcard and more than likely they do push play. How else do you think they do their mixing? Yep I know there is such a thing as an Internal Mixer and can be done manually within the software but by and large single output Soundcard users just line 'em up and let 'em rip. It is much easier to mix manually two sources with an external mixer than manually with an internal mixer.
I agree. There has been a number of DJs doing things wrong for a long time. My point was it didn't start these apps