|Chessical: Mackenzie soon gain equality against MacDonnell's slow opening (d3,c3,h3), and with <13...g5> he both prevents his opponent opening the <f> file, and secures it for his own doubled rooks.|
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<23...d5?!> seems wrong, as the <a> file will soon be opened, and the King would be more secure on <d7> with his Rooks able to content that file.
MacDonnell's <25.Bc5> is superfluous, he could have capitalised on Mackenzie's misjudgement about the <a> file with: <25. Rxa6> d4 26. cxd4 exd4 27. Rxc6 dxe3 28. fxe3 g4 29. h4 Rf2 30. Qa1
<27. f3!> would have stopped Mackenzie's King-side counter-play in its tracks as <27... g4> does not appear to be an answer <28. fxg4> hxg4 29. exd5 Nb8 30. dxe6+
The game swings back to Mackenzie after MacDonnell's slow <28. c4>. The straightforward <28. Rxc6> Kxc6 29. Qa6+ Kd7 30. Qxb5+ c6 31. Qb7+ Ke8 32. Qxc6+ Rfd7 33. dxe4 was much superior with a Bishop and two passed pawns for a Rook.
Grabbing a pawn with <35. Bxg5?> loses immediately to <35...Ne4>
Mackenzie's play deteriorates after failing to keep up an attacking initiative on the K-side. <37... hxg4!> 38. Rxg4 Nf5 39. Rxg5 Qh7 40. Rxe5 Nxe5 41. Qxe5 Nxe3 42. Qxe6+ Kf8 43. Qxe3 Qh4
<38....c6?> opens up the back ranks for MacDonnell's Rook.