The Service Center replaced the front half shafts after I demonstrated the shuddering to them. When I demonstrated it the shuddering wasn't very severe, which we chalked up to the battery charge being fairly low after driving 120 miles to get there.
Did they fix it?
Here's where it gets interesting. The short answer is yes. Hard acceleration no longer causes shuddering. But on the invoice was this gem:
Advise the customer not to accelerate hard in high suspension settings. On reading this I realized that when the shuddering seemed worst was when I got onto the highway leaving my grandson's martial arts lesson. And I have that location memorized for a VERY HIGH suspension setting to avoid contact with the parking blocks when I park.
Sure enough, I raised the suspension, accelerated hard, and
shudder! Back to normal or low height, no shudder. As I think about it, it makes sense due to the angle the half shafts have to make on high settings and the work the u-joints have to do at that angle. I may have also been causing undue wear on the u-joints with the very high setting and hard acceleration.
In my defense, there's nothing in the owner's manual about this limitation.