Wolves couldn't get in the game first half because we dominated it (right up to the goal).
It wasn't just the one sub that made the difference, Chavs came back in the game at the end of the first half when Tuchel dropped Mount into midfield, from this point they became more competitive and we found it harder to play through them (neither team had the upper hand at this point).
IN my view, it was a double whammy though, for us. I have to 2nd guess here but I feel Nuno took the right approach, to go for it first half and try to get a goal (something I might add only Liverpool has managed to score the one against them), then try to sit and play on the counter more (hopefully not on the edge of our box but aggressively as we did against City). We tanked after the first half-pressing (& that we also played Thursday whilst they played at home on Tuesday are all marginal gain in their favour, not ours) and when they scored from a set-piece we didn't have the bench to actually change and react (almost certainly had Berg & Lucas been available they would have been used for example and have enough quality to effect a game). 100% I'm not saying we would have won, I was completely expecting to get beat handsomely against them, I certainly didn't expect us to dominate/control any aspect of the game let alone do so in such a pro-active way that we did.
I don't dispute what you're saying. It just concerns me how easily Chelsea turned our upper hand on our head. We really were awful in the 2nd half and had no answer.
Touchel showed he is a tactical coach who is able to see if something isn't working and change it. Nuno keeps showing us that he starts a match with a plan and seems to not worry if it's not working.
Lastly, I thought our "dominance" over Wolves was too easy to put it down to us just being netter than them. We weren't exactly sprinting around and hounding them out. At times we were passing through them at walking pace and getting through. Then all of a sudden, they sparked into a life and from that point we had a few sporadic chances but were generally 2nd best all over the pitch.
And they made 9 changes from their PL squad. You'd argue based on appearances that our 11 that started was nearer the PL regulars.