--snip--

Thanks all - the cleat covers sound like the best (and most
cost-effective) solution. Assuming they are easy to source, I'll hit up
my LBS for a pair and see how they go......

** sound of brain whirring** - I wonder if there would be a market out
there for a "flat" (bmx??) pedal with a Look cleat attached underneath,
so you could ride your bike around wearing thongs/sandshoes/whatever
(**delicately stepping around appropriate cycling footwear
debate...**), and then easily remove it and use your normal cycling
shoes for when you wake up early and dress up in lycra.....??
Absent Husband