You be the judge! Here’s my situation. I have two identical DA10 cassettes - one for my training wheel and one for my Zipp disc. These were bought before I knew how easy it was to swap cassettes. I decide to sell my almost new race wheel cassette on eBay and went to put my training wheel cassette on my disc. The first 8 cogs go on ok. The ninth won’t go on. The splines look like the match up, but it doesn’t slide on easily. Both cassettes go on easily on my training wheel (open pro w/ DA9 hub), but only the newer cassette goes on my disc. I haven’t let my chain get past .75 before changing it out and I have maybe… 4500 miles on my cassette? I wipe down my chain after every ride and clean my chain (using one of those plastic chain scrubber thingies) once a week. Basically, I keep my drivetrain pretty clean.
The LBS recommends taking a rubber mallet to the ring that isn’t going on easily. I’m a little hesitant to take a hammer, albeit rubber, to a $1000+ wheel. Zipp wasn’t opposed to the rubber mallet idea when I talked to them, but was more under the assumption that my cassette has probably gotten malformed in some way. I would think that a DA component sould get more than 4500 miles on it, but maybe I’m wrong. I don’t ride particularly hard. Certainly, I’m in my middle gears more than on my 12t.
What does the ST jury think?