Since several people are actually praising the way Kiritoīs rl-kendo skills have been portrayed, I guess Iīll have to elaborate on why I hated it:

ALL skills within SAO were just that: "skills". RPG skills. Automatic skills. We had an episode where Kirito himself said that level is everything. THe higher your level, the stronger you are. Whatever fancy moves he showed within SAO were move patterns the game granted his "game character" due to rising in level. There is ZERO he could have taken to reality from that, because he didnīt learn how to move like that - he learned to activate the skills that MADE him move so.
When the episode started, I kept thinking "please donīt go there, please donīt go there", as I feared theyīd put such a bs stunt and have him use his in-game skills in rl. And then it happened. Kinda disheartening that Iīm the only one who found this to be ridiculous.
Of course, itīs made even worse since he spent 2 years in coma. He keeps telling his sister that he needs to re-grow muscles, but he certainly didnīt show - moving lightning-fast and almost beating the girl thatīs a highly skilled Kendo-fighter herself.

So, thatīs that. Guess itīs only me who had a problem with that scene. *shrugs*

Then thereīs the whole "guy whoīs planning to marry comatose Asuna"-plot line. WTF?! Agreed with Kraco: How does this guy picture his plans to work out? Unless heīs into corpse fucking, thereīs no way Asuna would ever accept him. Though itīs similar ridiculous that Asunaīs father agrees with these marriage plans.
Oh, but that was not enough: The author had to make this guy into some super evil, disgusting pig, licking his tongue in best Orochimaru-manner, sigh. That is leading to my general criticism for how things went:

WHY was it necessary to fill this anime with about all existing anime tropes? Even though there were a lot of silly things during the SAO-part of the anime, the rl-aftermath had such great potential. Why go with these already-been-there-elements (incest, evil guy, transferring vr-powers to rl), when this could have portrayed a realistic world and how these characters that weīve only seen as their online-personae interact within this different, less fantastic environment?

To give some details as for what I would have liked:
Kirito being physically frail, mentally depressed, and showing what a nerd he is (which I totally donīt get, when he has such a sweet, caring sister. Whatever). Trying to find Asuna. Asuna not being in a coma, but also looking for Kirito. Them meeting and feeling awkward. From here, the show could turn into something like CLANNAD After, where we see how the both of them manage real life, experiencing weird situations again and again due to their SAO-past. Then, at some point, when weīve seen how different rl is for the hero-couple, the main plot could return, being about finding Kabaya, involving new virtual worlds, but without being trapped inside them. Would have been extremely neat to have both rl- and vr-events intervine, like ... Asuna fighting her way in some new world created by Kabaya, whil Kirito is somewhere in Tokyo or whatever place and investigates stuff. They could then communicate through emails and such. Over time, the lines between rl and vr would start to fade and itīd all became just one big playground.

Yeah, thatīs what could have been. Instead the plot takes turns that make me even angrier than Sasukeīs weekly Sharingan-upgrades. :/