Oh and I also realized while testing the skill some effects:
- I put a variation of 5, since 10 was too much (if you had 11 HP and 8 SP, you would almost commit suicide

)
- is not possible to actually be the same value, since HP/SP values obviously can be not multiple of 5
so I added "until are about the same value" to the description!
Anyway after trying it in some test battles the skill is quite interesting, has several possible uses, as healing if you still have many SP or as SP regen if you have high HP. I am thinking if to make the skill progressive, so that for example if the gap is big, the step is higher: +/- 20, then +/- 10, then +/- 5 and so on. This way I could even reduce the change to 1-2 points and really have the same values (if possible).
The average could work but I think would be rather hard to understand for players - I think I would get many false bug reports
