Quote:During Karjakin's match preparations, he must not have been able to find anything new for White in the Marshall, or else he was not looking in that direction. So, he decided to play the most fashionable anti-Marshall lines, such as 6.d3 in game two, and 8.h3 followed by 9.d3 in (game four). ...
The position (after 13...h6 in game four) is a typical Ruy Lopez. For centuries, the classical way of playing the Ruy Lopez is for White to try to play c3 and d4, but now Black, with the Marshall pawn sacrifice ...d5, seems to be doing well. At least nobody has been able to break it down over many years. So lately White has started playing d3, a slower method with many different variations. It's clear that the lines with d3 should be less dangerous for Black, but it's a long game and White can still apply some pressure.
--Vladimir Kramnik in Alburt/Crumiller (2017) Carlsen vs Karjakin, pg.68-69
As Kramnik well knows, the rest of us are not playing for the World Championship, and can often win with something old.
I think what you are doing now is about optimal: play
both an anti-Marshall as well as some true Marshall line. The anti-Marshall option is practical for white, while the true Marshall option keeps black honest. I remember a long ago game Benjamin - Kamsky which began
1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 O-O. Benjamin annotated this with "Surely he's not going to play the Marshall?"
8.c3 d5 "He's not bluffing!" For white, being ready to play a true Marshall means being able to call any such bluff.
But the Marshall is highly impractical for black, who has to be ready to play a lot of sharp variations which rarely appear on the board. The true Marshall option forces black to keep doing this work, and you might catch out some players who haven't done it, or who have done it but can't remember it.