Mine had both days over the weekend naked,then today still in their middleweights! It's freezing here, or at least feels a lot colder because it's about 10 degrees colder than yesterday. None of mine are too hot. I look at the forecast every morning, and I am lucky that I have someone close by to off rug them if the weather gets warmer while I'm working.
I rugged up last night, left it until I absolutely had to go home, which wasn't long before dark, it was still 10 degrees when I left and I popped their middleweights on. But I knew within a short space it would drop down in temp and it did. It's still getting below 5 degrees over night and mine wouldn't cope with just lightweights on over night and with a small child I can't go back and rug them heavier later on if they needed it.
I'm sure some people probably go past sometimes and think they need rugs on or off, but fact is unless you live on site it's not always possible to go backwards and forwards to change rugs, sometimes you have to look forward and see how long they would be either too hot or too cold and weigh up which rug is best for them to be as comfortable as possible as soon as possible.