Doing without h3

One of the sins we commit as chess players is taking advice as 'read'. For as long as I can remember 9.d4 is the main line of the Ruy Lopez was not recommended, 'because Black plays 9 ... Bg4'. Instead 9.h3 followed by 10.d4 is considered best.
However, handled the correct way, playing d4 before h3 is probably as good as the main line. I tried it in my final round game of the Olympiad, and had quite a good position, until I fell apart after move 30. And going back 100 years, Capablanca showed and instructive way of handling the position, albeit in a slightly different line.
Allowing the bishop to go to g4, before hitting it with h3, gives Black the choice of returning along the diagonal, or moving back to h4. This was the choice of Capablanca's opponent, whereupon Capa played g4 (not worrying about king safety) and shifted play to the queenside, with Black effectively a piece down.


Capablanca,Jose Raul - Black,Roy Turnbull [C87]
New York Rice prel New York,NY (1), 1916