Why would I cap?

[Piiop]

Can't think of why. You say he's got you beat 100% of the time and won't fold.

If you are thinking to put the other player on tilt by trying to get him to fold, it's not worth it. When he does call the cap, you ensure that you lose 2 BB's and he gets the LAG's money. You don't want him to start calling YOU more cuz you'd rather be HU with the lag. The guy may not even tilt, anyway.

If you're thinking that it will encourage him to stay around longer, I doubt it would have any effect on that (other than he now has 2 more of your BB's).

Not seeing a reason to cap this.