Abda's 64% doesn't surprise me too much. Much of it is probably in fairly low player games where the enemy doesn't pack a medic and just gets steam rolled by critical rockets.
Of course this is another flawed value provided by HLStats, but you made a very good point there.
Since many of our games are pretty even and balanced (in general) most "blips" are actually very early or very late games with less players, where the skill of a single player has more impact than usual.
And if I recall correctly abda has quite often been early on the server, helping to get the ball rolling, so this could quite well be the result of that.