Can't get the Sleeping one.

Yes, the “L” is throwing me off.

eta: OH! Got it.

These are fun but sometimes I think my brain isn't half as smart as it once was. I can't get two of them.

I don't get the 'sleeping' one, or the 'Twins' one, either! My brain must truly be getting rusty! :^)

Rusty

Can't get number two but of course I'm assuming that I got the other ones right.

might be a giant surprise if I get them all ...

Okay, I looked them up and I think the Sleeping one isn't a common way to say that phrase. It would be more common if the word, "sleeping," was instead "asleep."

#2 would be impossible for anyone to get, IMO.

1. Backing Up
2. Sleeping at the Wheel
3. Quarterback
4. Coffee Break
5. Identical Twins
6. Count the Ways

I agree, asleep at the wheel makes more sense. When you posted ‘asleep’ I got it, even though ‘wee L‘ was a stretch too.

I'm not sure where these solutions are generated from. I agree, 'Asleep' certainly makes more sense than 'sleeping'. Perhaps 'sleeping' is the more common phrase where these are from. I couldn't figure out the Wee L either, until Outside mentioned it.

should be sleeping giant .... next to a little 'l'

I like bragu's answer better! :-))))