Yes, apparently I do My eldest GD told me to stop driving like an old granny (I was doing 40mph at the time - well, the car was anyway) and no, it didn't annoy me but more amused me.
Unless there are posted speed restrictions, I tend to let the road and weather conditions dictate how fast I will drive - something that youngsters don't always get to grips with and that may explain their irritation with older people.
Having said that, I think we have probably all seen, or been stuck behind someone, that never goes above 20mph regardless of the speed limit and that it irritating and dangerous if it forces other drivers to take reckless manouvres to be able to get past them.
Having just returned from having a young person in the car behind virtually in the car with me I accept I might have driving like a grandmother. After all it was a 30mph limit and I was doing 30mph. I didn't fancy his company even though he appeared to fancy mine so I pulled in and he shot past me like a bullet. Oh where are the speed cams when you want them?
so it was the mud and failure to notice it rather than the speed he was going at. I live down a single track road and drive a lot on those so I am always aware of there is likely to be mud even if there is no sign visible of course the NSL applies on these roads (i.e. 60mph) but no-one who is used to this type of road would even go at 30 mph if there were bends and 'mud' I suspect he was unused to these types of road, maybe forgot about the normal hazards that said he was not a grandmother and the accusation should not have been made given the choice - so long as the aged person was not poor of sight or co-ordination - I would rather be driven by a 'grandparent' than some fresh-faced know it all 18 year old who does not have the risk capability or experience.