The whole first season the man system worked great. No team really had an answer to break it until Yeo got 7 games in a row on it, and showed the whole NHL how to bust it up. It never recovered from there, though I'd argue the Avs gave up on it too soon. It needed some tweaks, but I don't think it needed abandoned.
I'm not saying Roy's system was better (though I think all the variations he used were, but that is a different debate). I said it was better for Varly. It helped him with his biggest weakness... puck tracking. It cleared lanes and pushed shots outside. If a NHL goalie can see a shot, they should be able to stop it at a very high rate. The results were there for that in 13-14.
I do think Varly has lost athleticism, and that is a part of his struggles now. That is what made him special, and it just isn't there anymore. He should be better than he is now from a talent perspective and part of that is on him. I do think a portion of his issue this year has to do with his poor puck tracking.
On a side note, I think Jose Theodore was the best goalie the Avs ever had in terms of pure athleticism (his mechanics weren't fine-tuned to say the least, plus he was pretty small as far as goalies go). He too faded quickly once injuries cut into that ability.
But I still don't think Roy's system worked "great." That team got annihilated on the shot clock every single night. They just happened to get great returns on the transition game (no one forced more turnovers in Avs history than Ryan O'Reilly) and were shooting the lights out percentage-wise. It wasn't just Yeo who figured it out, that wasn't going to last.
If there's one thing I wish Bednar would emphasize more it's the transition game. He has his teams give up WAY too much ice at the attacking zone blue line and the neutral zone instead of getting more aggressive and forcing turnovers. They have the personnel to absolutely kill the opposition, don't know why they don't take advantage. Again, I feel like part of this is Pratt having the forwards backcheck or just hang back entirely too much. If you've got a weapon like J.T. Compher, you f***ing use him. I also think Andrighetto would be great at this...it would certainly be a better use of his skills than making him try and play defense.
Also on a side note...is it just me or does Bednar & Co. seemingly call for changes at horrible times? I swear I don't recall a team that killed their own momentum so many times due to being called back for changes as much as this team does.