[{quoted}](name=The Last Ballad,realm=NA,application-id=3ErqAdtq,discussion-id=Tpohmyu8,comment-id=0001,timestamp=2017-03-04T19:00:44.500+0000)
Not only would this remove Cassiopeia's unique passive, but it would remove 5 unique or limited passives from the game. M pen is hard to get, being on only two items, one of which are boots. The extra mobility from mobility would be sorely missed, Tabi's % auto damage reduction would be a shame to miss, technicity is only on masteries, boots, and a Twisted Treeline exclusive. Summoner cdr is only on boots and masteries, and slow resist is the same.
In other words, a good thought, but would require items to replace the functions of boots, and at that point? Just keep them.
I kind of agree that each boots got quite an unique passive, but that's only to render those clunky item relevant, in your argument you don't even speak about the Move speed part of boots, which is their primary function.