Ah but my intention was then Nb4 with tempo as it hits the Queen,
then once she moves then that "trapped" Knight would go back to c2 and they would nicely support each other in enemy territory.
See annotation on move 20...Re8. I wasn't able to play Nb4 immediately purely as my Queen was undefended,
I missed that Bxa3 pins to an unprotected Queen. For this reason, the timing of Nxa3 was off,
and if I'd have realised this then yes he would have stayed strong on e3.
However I did a post-mortem through Fritz, and this was still ok (albeit not best).
The only real baddie was 22...Bc5 as this dropped the evaluation way back to over +3 in favour or white,
whereas 22...Nb4 instead would have made the score still equal (well, 0.42 I think it was).
I missed a tactic end of the day, guess this is hardly uncommon