Any question answered...

Where in the statement "you are right, ultimately it is his decision and if he insists on doing it my guilt will be minimised if something does happen" do you get the impression I will be telling him what to do?

It wasn't in that post, it was in your earlier one "How do I convince him to pay someone else to do such jobs?", but I was making a wider point.

would seriously consider shooting my father if it was a straight choice between that and going up a ladder

Hyperbole aside, you probably want to look at your problem before worrying too much about your dad. Either that or you can pay somebody to do the jobs you don't want your dad to do :)