For Caro-Kann Exchange Variation, is Bg4 pointless after white

Caro-Kann players, in the exchange variation what is the strategy when White moves 4. Nc3. Why is this a mistake, and what small edge can you gain from it? is it simply

Black responds to e4 with Caro-Kann, doesn't that take away White's right to play other openings? : r/chess

Discover the Secrets of Winning Chess Games

For Caro-Kann Exchange Variation, is Bg4 pointless after white takes exd5 and cxd5? Or is it better to move Bf5 since its less committal? : r/chess

More Ways To Battle The Caro-Kann

A Practical Black Repertoire With d5 c6 Vol 2 The Caro-Kann and Others Defences - Alexei Kornev PDF, PDF, Games Of Mental Skill

London System Tactics: Unleashing Opening Traps to Win - Remote Chess Academy

Charlotte Chess Center Blog: November 2017

Defensa caro kann bezgodov, alexey the extreme caro-kann (2014)

The Caro-Kann: Exchange Variation - TheChessWorld

Sicilian Defense: All You Need to Know - Remote Chess Academy

Chess openings: Caro-Kann, Classical (B18)

Sverre's Chess Corner: 2010