You are not "privileged". You are OBLIGATED to maintain course and speed if you're the stand-on vessel. This is the part of the rule that too many sail boaters don't understand. They have no "right" to cut in front of you, just because that's a convenient time to tack.
Well, not really. Rule 18a states that a power vessel shall give way to, among other things, a sailing vessel (under sail). There are some specific exceptions to this, but for the most part if a sailing vessel under sail tacks in front of you, even if you are the stand-on vessel, you need to give way to it. And since the sailing vessel is under sail, while they may be the give-way vessel, they can do what they please and are under no obligation that I see defined anywhere to continue their heading until the crossing has been completed.
I assume the thought behind the rule is that since they are at the "mercy" of a wind they can't control, their actions take priority. Unless one is on the sailboat, it's impssible to know what is governing their decisions and actions. So "rights" are not really part of the equation.
We have never found this to be an inconvenience. Five-mile wide Bellingham Bay is a popular place for sailboaters because it often has good wind. Having sailed boats and been a member of a racing crew for a few seasons in the 1980s, I don't find it difficult to anticipate what a sailboat in the vicinity of our boat might do.
Our policy is very simple. If a sailboat under sail is on a converging heading that will bring us close together, regardless of whether or not we are the stand-on vessel, when we get close enough to be fairly sure of the sailboat's intentions, we
always make a very obvious heading change to pass behind the sailboat even if at the moment it looks as though continuing on our heading will put us ahead of the sailboat by a bit.
I say obvious because we want the sailboat skipper to know what we're doing. So our initial heading change is done quickly and is about 30 degrees.
As we approach the sailboat we will start easing back toward our original heading so that we cross behind the sailboat within a reasonable distance for both of us.
If this cuts as much as a minute off our enroute time I would be surprised. As I said, we don't regard this as an inconvenience at all.
We have occasionally changed heading only to have the sailboat tack and go the other way. This is rare, though, particularly with a crewed sailboat, because we can see the crew getting ready to tack. But on the occasions where the tack is not forewarned, it's no problem to simply steer back toward our original heading and pass behind the sailboat.
Now if one is boating in a designated channel, which I assume much of the ICW, for example, is, this where the exceptions I mentioned in the first paragraph come into play, and it would be smart for powerboaters and sailboaters to know what they are.
To my wife and I, the Colregs that apply to our boat make sense and are logical. But, as a previous poster very correctly said, they depend on the logic, common sense, and self-responsibility of the folks driving the boats no matter what the propulsion means are and the relative positions of the vessels.