I'll have to watch it again, then. I felt it wasn't dangerous until Aldeweireld jumped for it and completely missed - if the man covering on the near side doesn't get his header, then it always gets exponentially harder to defend, even if you do stick to your man (toe on the ball can send it anywhere, etcetera).
I don't actually think Winks is capable of offering us control of the game the same way Dembele does just yet. No doubting he's an intelligent player (I agree that his freekick was magnificently smart), but it seems like there's just a lengthened reaction time in 50:50s and a slightly less coherent central midfield when he gets put on in Dembele's place. Might not be down to him at all (might be down to the team not being as used to playing with Winks next to Wanyama as it is to the Dembele-Wanyama pivot), but it's something to look out for and manage nonetheless - *especially* when, as you say, Dembele can't really last the full game most weekends.