FlareBlitz
Relaxed nature. Loves to eat.
Investing in HP (236 HP / 252 Def / 16 SpD Calm) over SpD (252 Def / 252 SpD Calm) reduces total special tankishness by around 7% and increases physical tankishness by about 9%. This means 240 HP / 252 Def / 16 SpD Calm is likely the most efficient spread from a mixed-defenses perspective, but since Blissey is a special wall, it could easily be argued that the 7%reduction in special tankishness is worth more than the 9% increase in physical tankishness. Both spreads have their merit; perhaps it would be best to just give the nod to one and offer the other a very strong AC mention. I would lean towards giving the 240 HP / 252 Def / 16 SpD spread the nod simply because it's more similar to the current spread on-site (and therefore more consistent with the role QC decided Blissey is meant to play).