His letter to the F1 principals follows the Nurburgring race, where McLaren's Kimi Raikkonen speared into the wall with failed suspension due to a tyre flat spot.
"If you are in any doubt about your car," he wrote, "you should always call it in."
Rather than a criticism of McLaren's decision to take the risk and leave Kimi on track, the letter has been interpreted as a reply to condemnation of Max's new single-tyre per race regulation.
"Most of us would probably have done the same (as McLaren) ... last weekend," Max Mosley continued to write.
He did, though, urge teams and tyre suppliers to remember their 'responsibilities,' and made note of race director Charlie Whiting's power to wave the black and orange 'pit immediately' flag.