Thank you for the response. I tried both manually keyframing every frame and baking the animation presented above but both methods give the same result as when exporting the animation without any baking. Unfortunately, the NLA trick still gives better results. I also tried using BVH export with those tips out of curiosity and it resulted in improvement over previous BVH export but still gives worse results than any ANIM export.
I started playing with making animations using new Bento bones lately and noticed a weird issue I haven't seen before. I've made an animation for a tail and uploaded it to SL but it somewhat degraded in quality. The first video is the animation as seen in Blender 2.78 and the second is inworld after export using Avastar 2RC9 .anim exporter option. I tried using BVH format but it completely scrambled up my animation to the point of not resembling the original one at all. The issue mostly appears in slower animations. I read somewhere that SL optimizes animations throwing out frames where there'