2006 Wimb SF
Nadal - 35.0%
Baghdatis - 24.7%
Again this is very high; on grass I have only two AM's higher for Nadal, both in '08, against Youzhny and Murray.
I don't think this is an accident or a quirk of the stats. Unforced errors, of course, will always be subjective, but Nadal also has objective stats that are off the charts at this Wimbledon.
I'm referring to his streak of 80 consecutive service holds, broken in the final. The record is 118 straight by Sampras. Since Pete's time there have been only a few streaks at Wimbledon better than Nadal's: Federer had 105 straight holds stretching across the 2003-04 Wimbledons; Karlovic got 80 straight in '09; and Isner and Mahut each got 85 straight in their match.
Nadal, with his serve, is the unlikeliest candidate to post such a streak. But these AM's show that he was playing at a very high level -- maybe playing "out of his mind," or zoning.
His stats so far support the argument that he reached his grasscourt peak in '08 and that in '06 he was already closer to that peak than is generally assumed. In the '06 final which he lost in 4 sets, he produced an AM of only 22.4%, but that was partly due to how nervous he was at the start, when he got bageled.