Could anyone recommend a good seated massage video? Seated/corporate massage was not covered in the course I did, but it's something I would like to learn. How does Raymond Blaylock's 'Seated Massage Techniques' compare with the 3 seated therapeutic massage videos by Ralph Stephens? If I want to become proficient in the various techniques used in chair massage, is it necessary to buy all 4 videos, or will Blaylock's video be sufficient? Thanks!