An arrow means an improvement, 100% of the time.. But what about the absence of an arrow?
With other skills, [no arrow]=[no improvement] is probably right 90% of the time.
But for experience, you cannot assume [no arrow]=[no improvement] because that's wrong probably 90% of the time.
So arrows are a lot less meaningful regarding experience.
errr.....what are you on about?
You said with other skills no arrow = no improvement most of the time, but that is completely wrong. If I train something, then that skill and all the secondary skills for that training, will DEFINITELY improve even if no arrow is shown.
An arrow does not signify improvement, it simply signifies change to the next number. So 7.9 to 8 would be an arrow. But 7.5 to 7.9 would not show an arrow.