I have heard from others that there is some kind of image throttling going on in viewers other than 2.0, a very misnamed term. I talked to someone who looked at what is going on and he said that yes, there is definitely some kind of throttling going on in the 1.x viewers, probably to reduce bandwidth costs. The new viewer is not open source, perhaps, he speculated because this is required to protect web based content. His belief is that LL has to get its bandwidth bills down, and that the new architecture does that, and the older ones are just being throttled.
I am not sure of this, but I have heard similar things from several technologically inclined people. I would be happy to be wrong, but suspect that if anything the situation is worse and that LL is deliberately trying to cripple old viewers.