Is it cheating?
Does it mean that the performance is no longer genuinely live?
Is it too close for comfort to the ‘k’ word?
Respectively answered.
Only in the same way that playing a synth that sounds like an orchestra is cheating....
Yeah it does. Unless you have a band playing all acoustic instruments..... depends on how small the nits you want to pick with this are.
Well, that depends on how much effort you put into the mix to make it sound original and not-midi..... and how creative you are with the live instrument you are playing.
As long as the venue and the audience are cool with it, you are fine. Yeah, I haven't played any live gigs in a very long time, but when I was playing and doing a solo act, or performance, I really liked using the backing tracks. I have played many a gig where it was me, a bar stool, an acoustic guitar and a mic. It's certainly a lot of fun doing it that way and also freeing. Example.... if you are staring a song and realize the audience isn't into it, you can cut it short and do something else or conversely, extend it if they are really into it. You are not tied down to a given song form by the constraints of the backing tracks.
But..... backing tracks, well recorded, sure do sound good.