When you do see the "You feel the hand of Tulkas helping your blow"
message, it's not the total melee damage bonus that is doubled. The
current weapon damage bonus is doubled, and the submastery damage bonus
is tripled. Damage from gloves, etc, is not affected.
if (magik(wisdom_scale(130) - m_ptr->level) && (p_ptr->grace > 1000))
msg_print("You feel the hand of Tulkas helping your blow.");
k += (o_ptr->to_d + p_ptr->to_d_melee) * 2;
else k += o_ptr->to_d + p_ptr->to_d_melee;
else k += o_ptr->to_d;
... later ...
k += p_ptr->to_d + p_ptr->to_d_melee;
if (get_weaponmastery_skill() != -1)
int lev = get_skill(get_weaponmastery_skill());
p_ptr->to_h_melee += lev;
p_ptr->to_d_melee += lev / 2;
I actually reviewed that section of the code two or three times over the
course of writing and updating the spoiler, trying to work out which
bonuses were added to which field where. After further review, though,
I think your analysis is the correct one. I've uploaded a corrected
version of the spoiler. We Apologize for the Error.(TM)