At Silverstone one tyre exploded during qualifying so they had a warning that all was not well. So far at the Nurburgring there have been no mishaps, so I guess they have some more confidence that things are better.

But my understanding is that the real improvement should come at the next race because Pirelli are changing the steel part of the tyre for one made of Kevlar. At least if that explodes it is supposed to be less dangerous if the bits hit another car or driver.