Hey,
I knew it didn't sound right. But, I was surprised. Found in chapter 18 page 3, it has some notes at the top of the page.
1. Never re-gap a used spark plug.
2. Never use wire brush to clean the plug.
3. Spark plug should be replaced every 12,000 miles.
This information pertains to the 2UZ-FE engine. There is an inspection procedure for the plugs as well, but I'm assuming that this is needed every few thousand or something.
Do any of you guys have the FSM? If so, check it out. I'm just reporting what the manual says. I do hear what you guys are saying about the plugs.
Anyway, catch you guys later.
Joe