Controversy brewing over tires once again as Pirelli changes the thickness off the tread layer by .04mm at the request of the Merc team after Barcelona testing .
Other teams are upset because the change is meant to reduce overheating , which was most acute at Mercedes where they saw heavy blistering when running on the newly laid track surface .

I think they may have a point because this was pushed through for what were called safety reasons , but Mercedes were the only ones to complain .