but I don't.

My wife drives our 2008 E320 Bluetec. I almost never do and being an automotive Luddite, I don't like it. She also chooses to have it dealer-serviced rather than letting me f... it up. The question then: Do those things even have a preglow system? She just jumps in, turns the key and it always starts. For those few times I start it, I always pause (out of habit I guess) before I start.