Also, what makes it "smooth" is the absence of per-person limits, typically
$100K per person.


But there is a maximum limit of $1,000,000 payout for all claims combined,
right?

Yes, if that's the smooth limit.

Wouldn't this result in a per person limit of sorts (at least as
far as the insurance company is concerned) if more than one passenger sued
the insurance company?

Effectively, yes, but there is no explicit per-person limit stated in the
policy. That's what makes it smooth, as I understand it.