Right.

He takes a breath and lets it out slowly, moving his good arm so he can gently rub Ianto's back through the soft fabric of his clothing.

"It would really help if you'd just trust me about these things instead of tricking me into letting you read me."

Then John withdraws his hand, and his tone changes to something firmer -- more no-nonsense. Something closer to giving instruction instead of asking.

"That trust needs to work both ways, alright? You are helping me fix my arm and that means I need to trust you to do it, and not listening to me is not helping me trust you. If this ends up infected or set wrong I'll just be in more pain later so we need to do this right the first time. Now right now I'm nauseous, a little dizzy, my focus keeps slipping and I'm really very tired but I'm pretty invested in not having to have my arm re-broken in a few weeks. So I need you to tell me -- if you touch me and you can feel my nausea and dizziness and whatever pain that stuff hasn't dulled, will you still be able to focus or not?"

If Ianto really thinks he can, fine. John isn't convinced but he can also stop him if he thinks Ianto is just going to pass out or throw up.