Attack speed reduction? Cool. Adaptive helm is a great example of a cool, situationally powerful effect. I like it a lot actually. Spirit Visage is either the only MR item you need, or you're wasting money on stats you don't want, IE any tank with no sustain. Warmoggs is great, but having 800 more hp only does so much when you get crit for 500 twice a second.
Don't be condescending because you disagree. My post is about powerful % based damage reduction and how they could balance tank items by finding a home for that on some of them and reducing the amount of armor pen/shred in the game, which would be an overall buff to the health of the game, in my opinion.