If you go up a level, say from 5th to 6th, guess what difference will there be to your health increase, with endurance of 55 compared to 60.
Forget what the book says. I have tried this myself and urge you to test it. Here are various results from levelling up from 5th to 6th level.
1) Endurance not selected as boosted attribute (End. stays at 55) gives +5 health
2) Endurance selected with x2 multiplier (End. rises to 57) gives +9 health
3) Endurance selected with x3 multiplier (End. rises to 58) gives +11 health
4) Endurance selected with x4 multiplier (End. rises to 59) gives +13 health
5) Endurance selected with x5 multiplier (End. rises to 60) gives +16 health
6) I never had a save-game that allowed me to test selecting endurance with no multiplier, but it would seem reasonable to assume it would be +7
So your health increase is +5 at endurance of 55, and +16 at Endurance of 60.
So what does this all mean. I started at level one with 35 endurance, which equals 70 starting health (that much is by the book). I took Endurance at each level-up with maximum x5 multipliers each time. I got health increases of 14,14,14,15,16. Even going from 35 to 40 endurance at level two got me 14 health.
My conclusion is this. If you want to maximise your health at each level, select endurance at x5 every time you level up, certainly when your level is still in single figures. It certainly appears that the most important thing to improve your health when levelling is the multiplier on Endurance when you level up, rather than the actual endurance level.
Going by the increases my character got, it seems to me an approximate guess as to how health is calculated at each level (at least up to level 6) can be stated roughly as:
5 plus twice the endurance multiplier if it is selected at level-up. That is not quite exact, because if you look at what happened to my character, it is one point less than that at lower levels, and one point higher at level 6.
To correct this I am guessing there is a very small +/- modification for your actual endurance level. -1 for every 10 points below 50 and +1 for every 10 points above 50. That would make every level I gained work out exactly right.
As I said before, try it yourself
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