That said, I know condescension when I read it. Words like “poser”, “all show no-go” and “those of us who understand the issues...” are not the sort that convey great openness to the idea that there might be more than one right answer to the question I originally posed. As another responder put it, “You take all the fun out of it....”
To call that out requires no decades-long study of material properties, merely the ability to recognize rhetoric. I’m quite happy to go toe to toe with someone who, intended or not, is talking down to me, and if Jeff is the sort of guy that I infer from your post, I’m sure his skin will be thick enough to accept it.
I apologize profusely if my choice of words came off as being condescending. That was not and never is my intent and seriously feel badly if that is how they were interpreted. That is not who I am.
Since those words are on the record within my posts and are being read as condescension, I would like to try to clarify the way those words are being used to perhaps disabuse you and others of the sense that I was being condescending in my comments. To begin with the words “poser”, “all show no-go” were not being applied to any person or poster. They were being applied to the color of a sail cloth. I was using the word 'poser' in its original context, meaning something that poses as something it is not. In this case, it is polyester sail cloth posing as organic sailcloth treated with tannins to prevent rot. My point being that in my opinion, aesthetically tanbark polyester reads as inauthentic. (We seem to agree on that point.)
Similarly the term 'all show and no go' does not refer to a person, but to a dyed polyester sail cloth. I picked up that term back when I raced motorcycles in the 1970's. I completed in classes where the bikes where the types of modifications were somewhat limited. Most of us showed up with utilitarian paint jobs since sooner or later we would be need to make repairs to a bit of road rash.
Every so often, a factory team or some privateer would show up with a bike that had a 'show' (as in car show) quality paint job. That paint job would be referred to as "all show and no go". Its the same with tanbark. Dying polyester does nothing good for the fabric. It is solely an aesthetic decision. By the very nature of any decision which is about a visual aesthetic while not altering the performance of the fabric in a positive way, it is about how appearance (show) and not about performance (go). There was no condescension meant by that, it was simply a short-hand to explain the relative value of Tanbark in terms of aesthetics vs. functionality. The relative importance of aesthetics vs. functionality is in the eye of the viewer of the sail, reader of the post, and purchaser of the sail in question.
The last phrase (“those of us who understand the issues...) is taken out of context. The whole sentence read, "The nice thing about subjective opinions, is that those of us who understand the issues with tanbark color Dacron and who are students of historical watercraft, are equally correct thinking of tanbark Dacron on a traditional boat in the same way we might think it to be as silly as adding tailfins on a minivan in an effort to create a retro look." and goes on to say that clearly opinions vary.
The point of that paragraph was to explain where I was coming from (i.e. that as someone who is aware of the technical issues with tanbark Dacron and as a student of working watercraft...) my opinions are grounded in that point of view. By acknowledging that this is a subjective opinion and that there are 'equally correct' opinions out there, it should allow someone reading this post to make their own subjective call and either discount my opinion because my basis for disparaging tanbark colored polyester is not relevant to them, or it might make them think now that I understand the basis of the comment I have a different view of the item in question. What it was not meant to do leave the impression that I am talking down to anyone.
And yes, you are correct that my comments are not as much fun as they might be. You will note that I actually put a 'like' on the post that said, "you take all the fun out of it....” because I do understand that my response is not as much fun as less an academic or technical response. I readily acknowledge that I do tend to be a bit of a curmudgeon in my signature. Almost by definition curmudgeons aren't much fun, and our opinions are by nature dour, but they are only opinions, and like any opinion, they are not necessarily necessarily universally right or wrong. Your opinion may vary and its no more right or wrong for your boat.
I would be curious to see the additional stretch/wear of dyed dacron expressed as a percentage over time. For some companies, the trade off seems to be worth it. Hobie has been using coloured sails for half a century. And you don't need to look too hard to find a Hobie Cat using it's original sails.
Is the extra stretch/wear really that big of a concern on the cruising oriented trailer sailers the OP has been looking at?
Before commenting on that quote, in terms of your yellow and red kayak sail, at least in my mind there are several differences between that and the tanbark polyester being discussed. From a technical standpoint, your sail is small, and fully battened, and the boat does not have lots of stability, so the loads are not likely to cause noticeable stretch. Plus your sail is optimized a reaching sail for a vessel where a little stretch is less detrimental. From an aesthetic standpoint, the yellow and red color are not pretending to be something that they aren't which takes the 'authenticity' issue off the table.
I can't give you a specific amount of added stetch. Sailcloth manufacturers used to publish stretch characteristics of their various sailcloths and I tried unsuccessfully to find that information. So this is more anecdotal than specific. Regarding Hobie sails, back in the mid-1970's I worked for a company in south Florida that literally sold Hobie cats by the rail car load. (There are few things hotter than unloading a freight care full of Hobie cats in Miami in summer, but that's another story.) At that time, people were starting to race Hobies seriously. Hobie offered all white sails and the more serious racers were buying them instead of colored ones since there seemed to be an opinion that the colored cloth sails did not point as high and needed to be depowered sooner. Going to white sails required a pretty serious commitment since it was a roughly $75 upcharge when a full set of color Hobie sails were under $300.
I later spoke with the man who owned and operated the company that was actually cutting the sails for Hobie. I asked him about that once. He confirmed that there was less stretch to the white cloths when new and an even greater advantage when the sail cloth had some age on it and explained why that was true. As others have noted, I have sailed on sunfish where the white panels looked pretty fresh and the colored panels were noticeably blown out.
Gaff rigs (in much the same way as the high aspect rations on Hobie cats) place a lot of load on their leeches. (primarily from the mix of the gaff acting as a lever and the difficulty in minimizing twist in order to point). In the days before polyester, gaffers had vertical panels to orient the fibers in a manner that best addresses these high loads. Since I tend to care about performance, even when sailing historic vessels, I personally would prefer not to use a structurally inferior product.
In the end, when it comes to subjective decisions, we all make decisions on what our priorities and tastes are. I have explained mine and anyone who has read my posts over time knows to filter my comments based on my priorities. But I also understand that my priorities are no more universal than saying that vanilla ice cream is always better than strawberry ice cream, and certainly do not see them as being somehow superior to someone else's priority.
EDIR: P.S. I stopped downstairs at the sail maker in my building and he will try to get you a hard number for that difference in stretch.