I have been learning piano for around four months now. After learning scale fingerings, and a few folk songs, I have recently focussed on a Bach Minuet. My goal is to build a repertoire which I can play to performance standard.
I have learned the piece of by heart and can play it reasonably well - a few random glitches here and there. I might add that I am a tenor sax player. I know exactly what I want, but try as I may I cannot get rid of these small little glitches.
Usually on sax I memorise a piece after one or two runs through no problem. This is more of a challenge for a harmony instrument, but I learnt this piece in two bar, then four bar phrases then put it all together.

Any advice on getting real performance fluency? I can hear what I want - just cant get there. Maybe too early in the game?

ZeroZero,
I found Bach's piece need much more time to get them to a performance standard than a pop piece, one wrong note or timing would destroy the whole piece. I till have to practice some Bach's I have started years ago. I think you are right about too early in the game. My only advice (taken from others in this forum) is slow-pratice and HS for Bach's.

Try playing each hand alone to a) clearly hear and master the different voices going on and b) find out which hand messes up when, is still too slow, needs more expression in parts, spoils the effect you're after etc.

Do you have a teacher? He/she might be able to help you.

Besides: have patience and work on it, Bach is difficult.

I can play each hand alone. As fow mistakes, they appear at random places, I can go back and play any section without flaw after one or two tries. Its getting an accurate flow that is the problem here

Bach pieces are hard to memorize especially, and some would take forever to learn. i've been working on that invention 9 for more than a month and still i cannot get it under fingers comfortably yet. it's a much harder piece for me among all Bach pieces i learned.

so, take your time and don't rush it. eventually, as you practice it long enough, you'll play it well.