I've never seen liquid wick its way up a drinking straw. I wonder how this occurs with a hollow cantilever shaft? If we are talking about a flat roof, I'll buy into capillary action, but not with a hollow tube.
I have used liquid stylus cleaners for nearly 30 years and have never had any problem. I'd say that the cartridge manufacturer is most likely concerned that there will be premature mechanical failure due to improper Stylast application and that they are using the capillary action statement as an excuse to address their warranty concerns. From a manufacturers standpoint, I'd want as many end users as possible away from the stylus tip. Denying warranty if cleaners are used reduces the likelyhood of early shaft breakage for those that may not know how to properly clean their stylus tip, break the shaft, and then try to make their mishap a warranty issue. How do you come across looking like a good guy if you deny a claim, even if you know it is a scam?
You can destroy a cartridge if you aren't applying the Stylast properly. It sounds like you haven't had any problems in the past ...
