Mike Avery wrote:

Oven thermostats, to be kind, suck rocks. Most are off by
considerable amounts, and many vary. So, you set your oven
to 350F and the next think you know, your bread has turned to
mahogany (the phrase one of my employees used to describe the
bread when he burned it. He's a used car salesman now.) The
oven shoots to 500, drops to 250, and then climbs to 450.
I've seen oven temperatures fluctuate all over the place.

Using an oven thermometer lets you know what is really
happening, and when you need to call the repairman.

I'm sure that's true. I've actually got one, myself. But I got it after my
oven started acting crazy to see what was going on (digital control was shot
-- I rent, and when I finally buy a place, we're going analogue ...).

I'd heartily recommend that someone get an oven thermometer if they're
experiencing problems, but I wouldn't tell a newbie that it's a required
piece of equipment before starting to bake.

--
Jef