Also: I picked up 4 dimmable UL-10 LED bulbs off of ebay to try to see how they might work in my CAN lights. Mostly to cut down on power and heat. What a weird test that was. The 4 bulbs only cost $16 total, so it was a worthwhile experiment. I replaced the 4 bulbs on the front part of my soffit with the LED bulbs. With the dimmer switch completely off, the first light actually came on when I put it in. I guess the dimmer does supply low current even when off. Odd. Then when I put in a second bulb, they both just kept blinking.
I just put 6 LEDs in my kitchen cans and installed a dimmer specifically rated for LEDs. Unfortunately I can't find a picture of the exact lights, but it's the bulb, transformer(?) and trim ring in one. The really nice thing about the install is that they can be installed in a standard 4" ceiling box as well. Wish I knew that in the first place and I wouldn't have installed cans. Anyway, I noticed that they only dim about halfway and then start flashing. It's very annoying. Sometimes, if I set the dimmer where I want it and THEN turn on the lights, they stay dimmed WITHOUT flashing, but not every time. It's SOOoooo confusing. LOGANESS wants them on full when she's cooking anyway, so I guess it really doesn't matter. And I like to eat, so I don't argue.
My point is that , yes, there have been issues with dimmers not actually turning off, other than incandescent bulbs, all the way.