I have a casual, unstructured blazer made from cotton. It has stitching around the cuffs. I took it to a tailor and he said that, if he were to shorten the sleeves, he'd have to pull the stitching out and you'd be able to see the holes from where the stitching used to be because the material is cotton (as opposed to the traditional wool that most blazers would be made from). Thus, he urged me not to mess with the sleeves.
I'm inclined to trust the guy because he's otherwise a good tailor, but wanted to get a second opinion here. Should I shorten the sleeves? Are the sleeves of a casual blazer supposed to be well-tailored the way you would with a regular blazer or should it be worn "casually" (i.e. untailored)?
This is the blazer in case you guys wanna see it. It's from Club Monaco.