Short Version: Wagner has a tactically sound but strategically dubious plan. They have placed most Russia forces in a dilemma as Wagener now controls their supply lines and Ukraine troops are in front of them. The most elite Wagner forces appear to be racing to Moscow with nothing to stop them. Tactically, this is a very risky, but very sound strategy if your goal is take Moscow with the small force that Wagner has available. But even assuming this all work out tactically, for it to work the way Wagner wants it to requires that a few thousands troops in Moscow brings the Russian government down. This was the same bet that Napoleon made and it did not work out. If Wagner takes Moscow but most people remain on the sidelines or loyal to Putin, they are then very spread out geographically with no obvious next move.