It could be, but if your temps are getting high so often you may want to look into your transmission cooling situation first. Heat is not your friend regardless of ATF.
I do I know I live in Southern AZ where it commonly hits 100F in the summer time. And my T4R will have close to 500lbs of armor on it soon. And I managed to pick the lightest thinnest ATF for my fluid. Doesn't seem to be a good mixture?