16. bxc6 was bad, u should have just left it. If he plays cxb5 that gives u a protected passed pawn and if axb5 also a semi-open file for your Rook.

Pointless, move 18 and still your whole Q Side remains untouched! (apart from Q of course).

if he plays half sensibly there's no chance of promotion.

Black might have been better to have retaken with the K, keeping the d8-rook active.

anything against Nd5 or Nb5?

22...Qxc6

Had Black retaken with the K on move 20, then 23...Qxc6 would have protected the bishop quite nicely (24.Rxa7?? Qb6 winning the rook).

Instead of 24...Be6, Black might have considered 24...Qc6, defending the vital c8-square, but also attacking the b7-rook. Note that the equally vital b8-square is also adequately defended by B and R. Neither N move (25.Nb5 or 25.Nd5) would help either owing to 25...BxN. White would have to drop his advanced c-pawn.

Ne7+ gets u your Q

26.Ne7+ Kf8 27.c8=Q+ Bxc8 28.Nxc8 Rxc8 29.Rxa7 Qb6 30.Rd7 Qb1 31.Kd1 Qb3+ 32.Ke1 Qxa4 and Black retains a sizeable advantage. Instead 26.Ne7+ Kf8 27.Nc6 Bc8 seems to hold for Black as well (28.Rxa7 Qxc6).

No that would have been an error: 28. Nb6 Bxb7 29. Nxa8 Qc6 traps N

An intriguing position. Can White maintain this bind?

This probably ought to have waited. For the moment, the f6-pawn is the ball-carrier, and would have been stopped by 29...g6, leaving White's f2-rook out of the play (as the annotator noted). Then Black could at his leisure begin driving back White's advanced troops by ...Ba6.