This is such a difficult one. Personally, just to throw something else into the mix, I was taught that a beautician works on a makeup or Skincare counter in a department store, and a beauty therapist provides treatments.
I personally feel that short courses aren't worth the paper they're written on, and encourage anyone who asks me to commit to the longest and most comprehensive course they can. I know some of you feel NVQ stands for "not very qualified" (!), but I studied NVQ 2&3 and can say that I was motivated, keen to learn, and feel I got an excellent education so please don't tar all NVQ students with the same brush!
I do feel there are some things that can easily be learn on a short course, but others cannot. In my day job I teach electrical facials and microdermabrasion for an equipment manufacturer. We only sell to people who have a qualification in electrical facial treatments. Unfortunately, because of the way things are going, people want to get into the industry quickly ad start making money immediately, so they find a 2 day course with no entry requirements, and come out of it fully insurable with a certificate. I'm sorry bit it's not possible to understand th science involved and the dangers involved in 2 days. So they come to me for their refresher training and it all becomes apparent that they haven't understood anything (or haven't even been taught it), and I have to start from scratch.
IT REALLY MAKES ME ANGRY!!!! So no, I don't feel one day courses are the best way to make anyone a professional therapist!! Sorry for the rant but I'm so sick of undoing other trainers bad teaching, and teaching the basics to "therapists" who are technically qualified. Suck it up, and go and find a course that will teach you properly.