Clarabit used book moves until move 16 which lead to a very dynamic position. Perhaps short castle looked a bit better.
A weak plan from Clarabit in the late middle game lead to what looked like a won ending, however BirdEng pointed out that tablebases said black had a draw on move 41 with Kd6. Neither Mediocre nor Clarabit uses tablebases, a bit lucky perhaps. :)