While it is true that those in 42354362 LB. armor should not be able to move like that, making the ring's effect requirements would make is useful to only the lightest of armor sets; and that is why I propose in alternate idea.
Instead of slapping on a sign that says, "You can only be this fat to flip." to the ring, why couldn't they just make it to where those wearing heavier sets of armor, and maybe some weapons, aren't able to utilize the ring. Implementing that would eliminate the possibility of running into those players with Havel, Golem, Smough, Black Iron, Stone, and any other ridiculously defensive/poise riddled armors running at top speed like they wore nothing at all, while still allowing those with light-medium armor sets to use its effects.
It may just be that I still want my Silly Bugger build to be able to flip into people in his Armor of Thorns, but I feel this is a much more acceptable solution. The idea would eliminate most reasonable complaints about the ring, and force people to choose between superior defense and poise, or superior movement. I, of course, don't really think that they are planning on implementing any changes to the ring in the near future; I just figured it would be something decent to have your all's thought on.