That's how to lose nearly 14 rating points; he should've been arrested for that.
After that, he picked himself up, beat Cambridge's Ashley Stewart in Round 4, won again in Round 5 and then took another half-point bye in Round 6 (don't know why - a heavy night's drinking?)
The next two rounds have been David's best. In Round 7 he beat a Spanish FM with Black in a French Milner-Barry Gambit (see below) and then drew with GM Womacka (Germany) in Round 8. Today, in the penultimate round, he faces another GM, Ralf Akesson from Sweden. Latest news (19.50 on Wednesday): David has just lost against GM Akesson.
So he's on 5 points out of 8, and one of only two untitled players in the top 72.
This was the position after Black's 26th move (Kh7). Despite his two-pawn advantage, David's position looks distinctly shaky. But Rybka gives Black a +1.26 advantage:
Clearly, great care still has to be taken. Eventually, after careful manoeuvring by Black, and the first time limit being reached after 40 moves, White resigned, having failed to improve his position.
The other Suffolk player, David Brown, suffered losses in his first three games in the five-round Challengers A section, but finished strongly with two wins.