Can't tell what speed it was but his initial launch throughout the grip limited phase and after was very strong indicating that the ICE was doing OK. At 100 km/h the MGUK would normally come in - I can't tell whether it worked initially and then gave up the ghost or if it just failed to kick in at all. I suppose it will become clear when the onboard footage emerges.
What is interesting is that Honda mentioned they were hurt by the red flags at Monza. This might be pointing at issues with heat soak while the car is stationary on the grid. That's when PU fluids see peak temperatures. At Monza he had high temperatures and ERS issues right after the re-start, at Mugello something happened right at the start, presumably ERS related again. It can't be a coincidence.
