I powered up my iPhone 3GS tonight and connected via my tether on my Gnex. I then played a Netflix movie to test it and it played thru without pause.
Interesting, if you wouldn't mind conducting a rudimentary test for me.... Try using a transcoding/streaming app such as airvideo or airplayit or plex and use the 3GS to stream a tv show or movie from your desktop/laptop on your home network through the gnex on 4G to the 3GS... this seems to be the only place where I consistently encounter the AP dropping issue. I tether my laptop and ipad2 while on the road to the gnex and can work fine for hours doing surfing/email/browsing... intermittent transfer activity... but when I open those apps and begin to stream a show transcoded from my desktop at home, the gnex just randomly stops transmitting data to the ipad2 probably about 80-90% of the time. It could be after 30 seconds, 3 minutes or 15 minutes. Tether stays on on the gnex, ipad2 says its still connected to the hotspot..... very frustrating as I used my Thunderbolt in this capacity at the gym 5 days a week previously without issue. I love this phone but this problem is maddening...
Also, what rom/kernel are you on ShinyTop?
I am currently on Liquidsmooth 1.25 (4.0.4) with Glados kernel 1.26 - stock speeds, no UV