How old is he. I was just comparing with mine on age.
I think hes looking ok. Id like more weight on. If you carry on with the extra feeding he'll be ok in no time. Its what happens when you reduce the food. I wouldnt do it yet.
On a slightly different note.
I was looking at a before and after picture someone posted up the other day on a site. It was of a tb. I was actually horrified by the comments. The before picture looked ok in my eyes. The after picture showed his ribs (10 × worse than your buddy). Yet people were saying how much better the horse looked for loosing the weight. Honestly i thought the horse looked dreadfully under weight. I must see things differently coming from a farming background.
Mine's a welsh cob and I'm not happy if I can't see the outline of a couple of ribs. I don't want them poking through his coat but I do want to be able to see they're there. If I can't feel them he's on a diet. It worries me how many people think that's a bad thing and that he looks better when he's too heavy. On a fit tb I'd certainly expect to see some ribs, but fit is the key word. Lean and muscled up is very different to thin and underfed.