Speed signs are only a guide to work from anyway......

I'm the same as some of the others, if it's a 100 zone, we do a 100+ 10% until recently, when the margins changed.
Now its the signed number + 5% and yes, i do tend to get nabbed once in a while.
I'd be mortified if i was holding up traffic, as i get the tom tits when someone does it to me.
The ol Jeep shuffles down a gear or two and gets itself over most climbs without issue or dropping under the magic number.
I might add here too, the CT behind the Jeep behaves very well, so towing at a decent speed is easy.