I think you may be confusing vaccination (against diseases such as distemper, parvovirus, etc) with worming, which is a different type of medication. There is no vaccination for worms, unfortunately.
So whilst I agree that probably the majority of dogs which are walked on our land are fully vaccinated, that does not mean that they are not carrying worms. In order to be sure that they were not carrying worms, they would need to have been wormed for all relevant types of worms, including tapeworm, within the last 3 months,
Unfortunately we are not at liberty to prevent people walking their dogs on our land; they are not trespassing, they are using rights of way. Some tourist-y areas do put up signs about welcoming 'wormed dogs under close control' but hereabouts all we are allowed to do is show gentle reminders about leashes for one month at lambing time.
I think you may also be assuming that Dan's note was directed only at you. It was I that used the red bold letters, so I took it that some of his 'tone it down please' was also directed at me. I wouldn't dream of taking offence at that gentle reminder; this is Dan and Rosemary's website, which they run as a public service at no cost to the forum users. We usually try to behave as though we are chatting with each other in Dan & Rosemary's living room, and show them and each other the respect that situation demands.
I am not aware at all of telling you how to behave with dogs which you keep entirely on your own land. My opener was phrased:
Please consider worming them for both round and tapeworm every three months, irrespective, unless you *never* take them on anyone else's ground.
'Please consider' is hardly dictating, I'd have said? Plus, as you say you never do take them on anyone else's ground, then it would not apply to you anyway.
I apologise for the bold red; I was trying to emphasise a fact and was not meaning to shout.
BH and I
are commercial farmers, in that we make our living (such as it is) from farming in the uplands of Cumbria. We are also humans making our way in this world. We try to farm with sensitivity to the environment and attention to the welfare and happiness of our livestock, and to the needs of other users of the space which we occupy and use. We try to treat our livestock, the environment and other people with respect and do expect the same. You won't want to agree with me, but so do most of the farmers I know - small family farmers, mostly, ekeing out an existence on the fells and uplands in the beautiful but harsh north of England.
You clearly feel very passionate about environmental damage, overuse of chemicals in medicine and agriculture. That's no bad thing. You'll find me speaking up against prophylactic routine use of antibiotics in many discussions on this forum, and taking part in conversations about how to control harmful weeds on farmland using means other than persistent and damaging chemicals. We've recently been considering the use of invasive fertility treatments, and whether they are ever justified, or only to save a bloodline or breed, or whether their use should be unlimited in agriculture, dog breeding, and other spheres. (I'm in the "natural is best" camp, myself, on the whole, but I do see the drivers for using these techniques to save breeds.)
In my own experience, over a lifetime in varied occupations and interests (it's BH is the lifetime farmer, I've only been at it for the last decade), it is generally unhelpful to make assumptions about people's beliefs and behaviours based on broad categorisation. Even when it is true, ranting and proselytising changes few, if any minds, where thoughtful, dignified and respectful discourse may influence. Just my opinion, of course, and you are entirely within your rights to disagree.