>>340285737
Was this from the EU instance? 
I did not have any issues with shaders at the prom despite being there for the beginning to the end completely uninterrupted, admittedly it is embarrassing how many people had horrifically optimized avatars (and not just being in the Very Poor range, things far worse than that) but for the most part performance was fine despite having the vast majority of people shown, silky smooth 20-30 fps!