If you've ever dabbled at PvP in Dark Souls, you'll notice that a lot of people you come across do a flip instead of a roll: the effect of the Dark Wood Grain Ring. The ring is so common in PvP now that it is considered a necessity by many, along with the Ring of Divine Favor and Protection, which rightly holds one of the top spots for best ring to use in a finished build.
This blog post is a discussion about the viability of NOT using the Dark Wood Grain Ring in PvP. We're going to assume that the player involved has the medium roll, because no one in their right mind should consider using the heavy roll in PvP (the speed penalty coupled by the extreme vulnerability of heavy rolls due to lack of invul frames makes it simply a bad idea) and the fast roll is for most intents and purposes identical to the flip roll.
I'm an avid user of the Dark Wood Grain Ring myself; but recently I've began questioning its practical application. PvP in Dark Souls tends to be an affair where backstab spamming is extremely popular, and rolling anywhere near the enemy tends to result in such a thing happening despite the supposed invincibility frames granted.
The other issue concerning the loss of the Dark Wood Grain Ring is the fact that it slows down movement speed. This should not be too much of a problem so long that neither player wants to run away; otherwise, the slower guy would be screwed. This means that the Dark Wood Grain Ring (or at least fastest movement speed) is very important in dynamic hunts and killing, which are common in Anor Londo and Sen's Fortress, while it's less essential in dueling places such as the Undead Burg and the Kiln of the First Flame.
I haven't not used the Dark Wood Grain Ring or the fast roll in PvP, and I will try it out soon.