Caveman Caro-Kann

This is the dangerous variation known as the Caveman Caro-Kann. Now if Black plays 5...Qb6, White has the sacrificial line 6.Bd3!, planning to give up the rook on a1 for a fierce attack. See Michael Goeller's article here. My question is, what if Black does something else? 5...f6 looks OK for example, just playing to undermine the White centre. Then there doesn't seem much of an advantage. But I can't even find this move on ChessBase. Any thoughts?

I play the caro-cann myself, but I stay away from the variations generally considered boring. Let me explain.

Thanks, fireflashghost. I think I'll take your advice and avoid the Bg5 variation - c4 instead looks a sound try for advantage. I want to stick to 4.h4 because at my lowly level many players reply with the natural-looking 4...h6 5.g4 Bh7?!, which is excellent for White. I've won quite a few games in this line.

The lines with Qb6 are very annoying for black, such as in the c4 variation after white plays Bg5