"you HAVE to move the e pawn to place a bishop on g4"
I don't see what you're seeing. I mean 5. ... Bg4 for black in the first diagram. Instead of 5. ... e6. This is a line I gave in my post, and I like it better for black than the line you gave.
About the concern of Loomis, I have sample game with the 5th move 5...Bg4.
"you HAVE to move the e pawn to place a bishop on g4"
I don't see what you're seeing. I mean 5. ... Bg4 for black in the first diagram. Instead of 5. ... e6. This is a line I gave in my post, and I like it better for black than the line you gave.