another piece of the puzzle

I am really confused now. SO, I teach beginners on monday nights and then after the class is over, we have open practice for anyone who wants to practice. I run miller on those nights and tony runs harley and I also run Deuce with lots of rewards. I take the course that Lori has set up (no numbers) and make up a course for the diehards to do. I try to make it fun and challenging. For example, tonight, Jan was getting ready for a NADAC weekend so we made a fun flowing course that didn't have weaves (but did have table and teeter, whoops). He needed contact practice so I wanted him to have as much contact work as possible. After she ran Mac through a couple of times, I ran Deuce through with stops along they way and rewards for good performances. It was an 18 obstacle course (except I didn't do the a-frame). He ran it with drive and enthusiausm like I only see on monday nights. So what is the difference? One difference is the whippet girls aren't there, which he is just going to have to get over. Another difference is that the other puppies aren't there for me to compare his performance to (yes, I am human and am competitive but should give it up, they are border collies, different ballgame). We aren't doing drill work either, but I am breaking down the courses fairly small, into four or so obstacle blocks with rewards. He did leave twice tonight to go see Harley, but both times when he did, I walked towards the car and he came running. I guess I am very puzzled as to what is going on. Very obviously, I am putting some unknown pressure on him. I have to figure this out, this is driving me crazy! I LOVED his running tonight!!! Great speed on contacts, great speed on jumps, wonderful turns. So what am I missing?