To me, that's would be a pretty amateur move.
Um no. Professional labels do this all the time pretty much as standard practice for live album releases, we are the amateurs. A professional outfit would either patch it seamlessly, cut it, or not release it at all.. but really, what does that matter for us?
With the exception that I've seen you mic up a stage and you're no amateur
, I agree with your comment as long as you change the context of this OPs question. But the question asked for opinions about patching a single song from a different show into his live show recording. If a professional outfit such as Live Phish recorded a complete show and put that show out billed as such, but patched in a single song from a different date and venue (other than providing it as filler), I'd consider that an amateur move. (Album Title...Jimi Hendrix at Berkely
except for track three which was actually Foxy Lady, but this version is from Hawaii not Berkely) While I have plenty of live albums that are patched together and the liner notes say...recorded on tour between X and Y dates, I can't think of a single album I have that says recorded on X date, except for track Y which was from a different night.
That said, given that I used Hendrix as my example above, I'll add some context by saying that I, of course, realize that the original Hendrix Woodstock CD was released as a bastardized version that had the tracks jumbled up and some tracks were missing. But it was a beautiful thing when the family (aka Experience Hendrix) finally released the show almost completely intact, though I note the new version was still missing a couple of songs and that the opening track on that version which included some Hendrix banter was patched in from another source in order to make the enitre recording a complete and intact record of that historic event.