Riot balance team at is again...okay, asking calming "Why?"

Tank supports have taken the top place as supports with Leona leading the charge followed by Taric, Shen, Alistar and Blitzcrank

Time to nerf all shields and heals.

I would like to have a rioter come and explain the reasoning behind this set of nerfs to all items that grant healing/shielding power. I'm really confused as to this move as I see no reason for it. I'll keep an open mind I promise, but I need you to explain why you are reducing all 10% heal and shield items to 8%, idol to 5% and mikael's to 15%. What is the reasoning for this? I mean, enchanters have already been getting pushed out due to very strong rune combinations for tank supports. The top 5 supports are all tank supports that do not use %shield/heal power. Why are we kicking a class (enchanter) down further when they are already showing a weaker presence? Could we get some context for why these nerfs are needed?