[V8] plug gap

[dsaad at icehouse.net]

I was changing the oil and air filter last night, and decided to have a look at
the plugs. They are the OEM Bosch and have somewhere around 20+K miles on them.
They are dry but have caked on deposits. They always look this way btw.
The center electrode is a little rounded toward the ground electrode - as
expected from a used plug but more than I would have expected for a plug that is
supposed to last 100K miles.
Normally I don't bother checking the gap because I figure the electronic
ignition does not care too much about small gap differences. The spec is .032
and I guess they were around .040. I re-gapped to a tight .035 - because that is
the closest size I have available and now I see very noticable improvement is
both smoothness and power.
I am just wondering if anyone else has seen this much sensitivity to plug gap?
I am going to start checking it more often.

Dave