You're not missing anything. Lighting pops one-by-one (as the pop value goes up) was a Pat Lawlor obsession. I've never understood it. I haven't met very many pop bumper rules I thought were very interesting. One of the Bozo awards is "pops at max" and when I get it I feel like it's pretty much a "non-award".
After 8 years of owning the machine I still don't know how to light the pop bumpers, probably because I just can't get myself to care.
Another mystery; What relights the tombstones? I know starting a new ball will usually randomly light a couple up, and one of the Bozo awards is "light all tombstones", but beyond that I have never been able to figure it out.
For the first few years I owned the machine I couldn't figure out how to light the "advance tombstone value" award, but I finally did figure that one out (left return lane). The return lane is unmarked and does not have an insert to indicate that it does anything at all.
I suppose I should play my games with the glass off a little more often.