There are expert Cattleya growers who have written that they identify particular Cattleyas with thick, particularly double sheaths that need to be cut across above the buds so that the bloom spike and buds can emerge unhindered. I have a healthy Cattleya labiata with very thick double sheath and the buds cannot fully make it out of the sheath unaided. If the sheath has been opened, you don’t want to water the sheath and get water down in the buds.