I'm with you too Nebs

I have a great sail mast combination, same brand. What happens when my sail wears out, the mast should still be good as gold, if I change sail brand the mast may not be a good match up I just can't afford a new sail mast combo every time, so I'll stick with the devil I know.

The problem with this 'standardized mast" argument is that it would come at a large cost. If you have done any actual mast testing (as I have) you soon find that manufacturing tolerances are often not good enough to keep the bend within a couple of percentage points or a couple of IMCS numbers. That is from one manufacturer using the same materials, techniques and mandrels. To keep this variability smaller costs more money, and arguably has very little benefit.
The best sailmakers, IMHO, make their sails in such a way that these small variations do not harm performance. This also has the advantage of making their sails work well on a variety of slightly different masts with very similar, but not identical, specifications. Of course, there will often be an absolute optimum mast for any given sail, but as the Boards magazine team found in their testing, it is not always the mast the manufacturer specifies. Different things work better for different people. Since I am smaller and lighter than many of the Pros who do the development testing for most sailmakers, I often find slightly softer masts work better for me than the standard recommended stiffness. Try going into your local shop and asking for a 400/18 mast. "No can do sir - standard masts are 400/19". It's like everything else really. If it matters to you enough you will make the effort to find that 400/18 and look after it lovingly. Just as well there is enough variability in masts that I have managed to find just such a mast on the edge of the production tolerances. Now I am looking for one with just a touch more stiffness in the top curve........ :-)

Mast manufacturers are competitive as well. They look for things that might set their product apart, that might make it work better. They use different techniques to try to get a cost/performance advantage. The science and art of mast design progresses and we all benefit from the competition.

I agree wholeheartedly with the sentiment that there should be more IMCS mast curve labeling. I don't really understand why this aspect has been neglected by the mast manufacturers when they all still give the IMCS stiffness rating. Rather than rant here we should all be flooding letters to our mast and sail suppliers demanding better labeling. I think I'll shoot a few letters of myself pronto.....