Reading through all the posts on this topic, especially those from legal professionals, has made several things compellingly clear. Cut through the qualifications and fine points, and you are left with a few basics:
nothing is ever guaranteed or final
each case is its own separate reality
judges and juries have enormous latitude
you always can be sued no matter what. Final outcomes, probability of dismissal, etc., are not relevant to the requirement that a complaint be formally answered, the expenses of which must be paid by someone; the defendant directly, the population which pays insurance premiums, and society in general because of the increased costs of doing business
the trend is very strongly in the direction of expanding definitions of liability and increasing degrees of financial risk.
To say that high blanket insurance coverage is the answer is like saying that the answer to increasing levels of violence is the emploment of armed bodyguards. Ultimately, there is no real protection from the tyranny of the civil litigation system, other than having no assets. Case law, precedents, and similar guides can never be relied upon absolutely. Your situation may be the one which becomes new precedent.
I like Jonathan Swift's definition of precedent: "a wrong which, having been once committed, may thenceforth be repeated."
There are a number of primitive peoples who believe that all death and illness is caused by malice, black magic and spells. All misfortune, therefore, has an author, a culpable individual who must be punished and who must make restitution. Our civil litigation structures seem to be devolving into a system based on similar logic.