I hear what you say regarding the performance but I think I can confidently say it was due to two factors:
1) Reece James is far from being as dynamic and adventourous on that side as CHO. It was clear from the Burnley match that our attacks that were mostly coming down from that flank mostly petered out upon his arrival. Added to that Alonso, who offers almost nothing apart from languid pass backs in open play on the left side means we were largely toothless. In the 3-4-3 formation (think Victor Moses goals during the Conte era) the wide players in the midfield 4 get opportunities for space and goals. That is also why despite Chillwell’s current relegation, his pace and better capacity for adventurism is preferable to Alonso - or play CHO on the left and Reece James on the right would make the best fit.
2) As some have already pointed out, CHO should not be given “in-field”duties and should be out wide. He was pretty dire with low intelligence running and off-the-ball - almost Willian-esque.
I believe Tuchuel would have spotted these as his decisions have been astute so far.
I would also comment on what you said regarding the midfield and, if you are correct, then TT would think himself blessed to have Kova in his team. In the area of line breaking (rugby term)- close control - ball carrying midfielders, he is a class apart. If his final ball was better, he would be attaining legend status.