To explain this, Willpower adds to Bonus Damage at a slower rate than Power does. Willpower is only more valuable because it also adds to crit rate (at a substantially diminished rate compared to Crit rating, but also on a completely different DR curve that is *way* more shallow than any other). When WP gets sufficiently high, the diminishing returns on Willpower's crit contribution will reduce the benefit such that the Bonus Damage contributions are the only appreciable addition and, as such, Power becomes more valuable.
Well yes that is exactly how Willpower v Power works, as is explained in the OP. My question was when MS it would 'theoretically' overtake power. The question has been answered, even though an actual calculation would be nice. You just told me what I already knew and did not ask for.
And it is very useful, I am now running at 250ish crit rating but still have 40% crti, just because of all that MS. meaning I have a **** tonne of free rating all dedicated to power.
Also anyone know the number for Sentinels/Shadows, i.e. classes without mainstat buffs in tree.