Timeless has started to become stable, I think its time to do some performance optimization. I guess this could be a tracking bug once different performance metrics/issues are identified.
At T217883 its claimed
As it stands, the CSS included in Timeless exceeds that of Vector by 5kb.
In my test, I got closer to 4, but its clear that the css foot print is slightly larger in Timeless then in vector. This may be related to having more images embedded in the CSS which probably don't gzip well.
More to the point, in initial tests, (uncached) Timeless seems to be behind Vector by about 0.1 seconds both on cable internet and 3g ( cable: vector, timeless. 3g: vector timeless. 2g vector, timeless).).
On the backend side, In very initial profiling (very low sample size of 1), Timeless seems to be about 0.1 seconds slower than Vector, and 0.3 seconds faster than monobook. (Link to profile: timeless, vector, monobook)
Anyways, that's very initial. We should do more profiling and stuff.