Having flown the YAK-50 myself I think the Pilot did very well and would also like to thank him for putting that video into the public domain. One can get instruction, read manuals and so on but to see a real situation unfold is very informative and thought provoking.
As mentioned above, standard procedure is to leave the gear up when making a forced landing to mitigate risk of nosing over. Looking at the video the aircraft did float a long way at the end. With the gear up there would have been less drag than normal, which could have been a factor. We dont get to practice that bit !.