If someone comes to S2 with a manicure certificate in hand, we have to assume they took a manicure course. They cannot buy without it. Blame the schools for teaching bad courses ... As for S2 they won't let anyone do a Shellac course unless the person has already got a manicure certificate so naturally on certain Shellac courses S2 do not teach manicuring as it is taken for granted you know how to do it for goodness sakes.
The CND manicuring course is fantastic and one of, if not the best and most comple thatte agvailable. If people take the CND manicuring course, they damned well know what they are doing and how and why. But many decide not to pay for a quality course and go elsewhere for the manicuring and come back for Shellac when they have done it. Can't police every course to see if it meets CND standards because they won't. The industry is what it is and it's not perfect by any means.