There may also be a strain thing there, [member=26580]Backinwellies[/member], do you think? In that some Dexters are run as pure sucklers, and a suckler cow's job is to look after her calf, ideally in the context of a relatively self-sufficient herd. So a good suckler cow is often fairly independant-minded, putting her and her calf's safety above any other consideration. (Bit like a hill ewe.) Whereas a dairy cow - or a house or crofter's cow - is bred for docility and biddability. Even if she gets to rear her calf, she is expected to look to her human staff to meet her needs, and to expect them to keep her and her calf safe.
So a Dexter from a pure suckler herd may be a more aloof and independent animal than one from a smallholding where they get milked? I have certainly seen that with Galloways. Some - most, up where I was in the North of England and across the border, actually - seem to be pretty much semi-feral, and that is consistent with doing their job out on the fells, moorlands and hills. But I met others who are housed over winter, some were milked, and they were as handlable and soppy as any Jersey.
And perhaps the same could be true with some Shetlands. I did actually explore getting Shetlands for us here when Hillie died, but our local breeder runs hers as a pure suckler herd, and although she was confident she could pick us quiet ones, she couldn't vouch for whether they would settle into a dairy routine.
Oh, and the first time I had to hold a 5-day-old calf down while its eartags were put in, was in front of its British White mother, who didn't know me from Adam (although she did know the person wielding the taggers.) My accomplice told me that the cow would be fine, and she was.