Connected to this thread, I went to the rehearsal of this newly-forming fusion band last week (our concert band conductor put me onto it). They were friendly guys (keys, drums, bass, lead electric guitar), though the leader (keyboardist) was a little detached.
The village hall they practise in is about 35 - 40 minutes drive, in the middle of nowhere, no street lighting and would be a pig to get to in winter.
Anyway, as I predicted, these guys played from knowledge of chords and all by ear, as most outfits do (they are not readers - the keys can read a bit) and of course, all in concert pitch. They started with Chicago Song and gave me the Aebersold sheet - which isn't the same length as the recording (oh, this band likes things to be just like the record) but at least available in Eb. I actually used the handwritten transposition I did myself from a concert pitch transcription of the recording I found online. They put me on a mic - though I never mic my sax and indeed, even with their amplified instruments, it wasn't really necessary IMO, I was plenty audible.
I played the sax part okay, after all, it's the same thing over and over but when it came to my 32 bar solo, I of course couldn't play exactly like the Sanborn funk thing, so just did my own far-out thing. I just can't count bars whilst improvising, no matter how I try. So I did what I could, the number of run throughs we had.
That said, I have been improvising okay when soloing in concert band if we play something like Rock Around the Clock and on Saturday, I launched into an improv on a pop tune and I went to that place someone like Sonny has reported he goes to when playing, when you're into something else but snapped back to the tune when the backing track needed it.
Put It Where You Want It, they gave me the fake book of it - concert pitch - so I scribbled the transposition out of part of the tune (from my handy ready reckoner) but having never played it before, I didn't do much and they didn't stick to the overall geography of the fake book and I sat out on the soloing.
Then they tried a tune without a title by the keyboardist. The 'sheet music' was just a list of the chord names, the bass note names and a list of when Intro/Verse/Chorus came in - again in concert pitch - and one was expected to play the tune, when it wasn't demonstrated. I got him to demo his themes but it's not easy to pick out a tune you've never heard before (though I've played my own tunes invented on-the-spot and transcribed many times).
The bassist - who also wasn't playing all the lines - had to go, so without him, they ran through Pick Up The Pieces - I handled the repetetive (and boring!) riffs okay but again, the solo parts got me.
I'd explained on the phone that sheet music is my crutch, even though I can readily play many tunes without music, I often have it in front of me (when playing to backing tracks) and of course in concert band (and big bands, for instance), sheet music is de rigeur. I explained this again. I had been playing, when warming up, St. Thomas - of course by ear - so they keyboardist found the tune in his fake book, to play along (the shoe was on the other foot now!). Of course, it was a different key to the one I play it in, so I about got it right. I asked the drummer (who usually plays thrash metal) to give me a calypso and he didn't know what it was.
I then asked for a swing rhythm (having to explain 'ten-to-ten') and I played just with drums on East of the Sun, in my semi-Bird style.
I may have been playing sax for over twelve years - and playing music since the seventies - and teaching it for over four (where I stress my students should learn all their scales, arpeggios and play without music when memorised!) but I know I will never be able to make that intuitive leap to the state needed for a band like this, no matter how hard I shed. I cannot recall all scales, modes, chords nor able to transpose on-the-spot, especially when playing without music or counting bars when improvising. My brain is just not hard wired for it, full stop. People love my playing, I won a busking festival in the summer (as posted before), so shouldn't that be good enough?
I phoned the guy the night after and said I just couldn't cut it (they loved my tone etc. and I must stress they were not unkind at all about my soloing problems, quite the opposite in fact) and resign myself to playing solo to backing tracks for the rest of my natural and with concert band. I'm playing solo gigs and teaching every other night anyhow, so I'll have my Wednesdays back!