@fais : you cannot have an honest opinion unless you have been following them recently
. I am not taking a side on who should be selected but the fact of the matter is recently Xu Xin messed it up by losing foreigners in the olympic qualifiers. I know ZJK lost recently too but that was against Dima who he beat in the tournament before. LGL's analysis is that ZJK lost because he was over confident and he even said that right after the match not just now to justify the selection. Regarding ZJK's stagnation , I agree he had stagnated but not in recent times , it was in the period before an year back and LGL had said so as well.
Recently he has added much more variety to his serve receive , doing really good pushes and flicks off the forehand.
Again , I don't think ZJK has been selected for the olympics , its yet to be finalized.
ZJK does have more upsets against foreigners and the coaches accept that, but the coaching team thinks that he is a not the same player mentally as the other two. They think unless ZJK is under pressure he really does not focus. The only think he really had to prove was that he could play non-stop this year and make sure that he shows that he can withstand the pressure physically and not lose to lower ranked players.
Also , there is the prospect of winning two grand slams, with ZJK and ML its a win win situation , if ZJK wins he wins two grand slams , if ML wins he wins his first grand slam. With Xu Xin , there is a win lose scenario where where if Xu Xin wins, ML does not get the grand slam. So I think , the coaching stuff prefers the win win situation, they don't believe anybody in the world other than ZJK can beat ML in a major tournament . They know the gold is already theirs , its just history they are after ...
XX strong appearance in doubles may also be his undoing. Sadly, ZJK doesn't need to be better at singles than XX, just suck more than XX at doubles.
I haven't had a chance to really follow the three, but my take so far is that XX and ML have really come a long way, ZJK has mostly stagnated IMHO, and I don't think he should be rewarded for that.
Also, XX just seams to have a better track record against non Chinese players (downright brutal), where as ZJK has had more upsets (again, this is my perception, as I haven't had a chance to follow them closely).
Finally, their ability to beat each other is irrelevant, as the objective is to secure team medals. (Whether ML gets gold or XX gets gold is irrelevant as long as China brings home the gold.)