You are pretty much spot on.
If I'm just out for a wee mooch, it's fine, as I'm more there for the hunt, than the catch. So, one runner is fine, and to be honest, he hunts very well, so he's more part of the pack, rather than just waiting to run.
However, you'd be surprised how well he does, as he's used to working with them, so knows where to put himself. A lot of the time he's hunting up with the hound and terriers, so when something lifts in front of them in the woodland, he will just try to steam ahead and run it down.
Obviously if doing covers, he's sometimes unlucky on his pi