How Is Spin(Aka Slide) Attack Dmg Calculated, What Mods Affect It?

[Monolake]

I want to know how is spin(also known as slide) attack damage is calculated and what mods affect it. 

Apart from general melee dmg mods (Pressure Point and Spoiled Strike), what other mods increase it. Do elemental dmg mods stack at all? Does crit proc on this attack and is crit chance same as for normal attack? 

What type of damage is it (impact/punctiure/slash)

Sadly, the game doesn't  show all the numbers for spin attack (and neither for charge ) for weapons. 

 

I really like this type of attack and want to maximise its damage and effectiveness. 

[Xrylene]

As a general rule, spinning attacks seem to deal around double the damage of normal melee swings, and I think sometimes deals more in the case of certain weapons. Seeing as they are obviously not charge attacks, I believe they would be affected by any mod that would affect normal swings, but with a higher base number to work off of. Stuff like pressure point and elementals would work nicely. The damage type that it does would probably be the same ratios as the weapon's normal attack, so in most cases primarily slashing. Lastly, I believe it can crit, but you really shouldn't bother with crit, especially on melee where the bonuses and base values tend to be insignificant.