[pasbesoin]

With that low a rate of engagement, depending upon the topic material I'd be concerned with the amount of time it will take even a very competent developer to refresh their memory and get back "into the zone" on this particular product.

Sometimes, it's easier to have more work, simply because you can stay focused on it long enough to get more done and/or to think about it more thoroughly/deeply.

It's just one item, but perhaps take a look at whether you could adjust your development cycle for this fellow to accomodate more useful, efficient sustained bursts.

(Again, I don't know what the specific work in question is. The pertinence of my comment is therefore unclear.)

P.S. Your use of the word "dick" indicates that you are already emotionally engaged in this topic. Beware. No one's Mister Spock, but if you're letting your emotions lead, you may be heading for a mess. Also, if I were the developer and saw your use of the word "dick", our relationship would be over.

In short, you seem to be dragging some of your own baggage and/or faults into this.