MidnightDuffer: It would be interesting to compare this Bird's opening to others, I think, they are playing it close to the book.
On another subject, dog gone,
White is down 2 pawns, Move 29. Should be 29. Rxe4! getting one pawn back and possibly another in site, the King would have to come out and defend the pawn on e6, Black's Knight is not very mobile, the Black Rook at a8 has not gotten into the game yet nor the a and b7 pawns, this endgame would be better to have the Bishop with I would surmise! Caveney's selection is in error, 29. Rg1? A blunder;
36. Kd2? again, falls short; leaving the f4 pawn unprotected in what now seems to be a race to pawn promotion with the Rooks traded off the board; Black's move 36. ... Kf3; is the best move instead of taking the pawn, the pawn on e5 now, which could have been snatched on move 29. is threatening to become a Queen and it should not be that hard to get it down there.
36. Be5, protect the f4 pawn even if it means the King will eventually get the h pawn... White's last chance to save this game with at least a draw.
One can not assume Caveney would have not lost; but it would have been more of a battle.