Yep, forgot about the ARC10.... When he got the bronze medal at the OG2008, he had BG65 at 31x35lbs. http://www.yonex.cn/news/show_news.asp?id=591&type_id=1
I think the chart shows the tension as a range, as in Chen Jin used a tension between 31 to 35 lbs as opposed to 31x35lbs.
Whadda ya know: a whole thread about players and their racquets http://www.badmintoncentral.com/forums/showthread.php?t=2306
It doesn't really seem unusual to have a 4lb difference, especially when you're going up to 30+ lbs....though most other have it just at 2lbs difference. Either way, tension is at like 30+lbs.
The frame will distort and eventually collapse, even after being strung not long ago and in the middle of a match. There's a reason why the tournament stringers all string to uniform tensions for both the main and cross strings.