This has worked out as a good scheduling decision from Dave. He has played 3 unranked players and the WR 521 and gets 10 ranking points for it. Unfortunately he should play Gilles Muller next
Or (while I take your point, Stircrazy), you could say that there's something rather lovely about a system which gives a player ranked 593 the opportunity to play someone who a week ago was battling it out with Lleyton Hewitt on a televised court at the US Open .....
If he just goes out and plays without thinking about the disparity in their rankings, he should be fine. The difficulties can come if you have time to muller over the situation.