Dover Saddlery saddle fitter?

My saddle no longer fits my horse. As a youngster it fit him nicely but over the past few years his body has changed and he has gotten much taller and has developed much more muscle. The saddle is starting to pinch his back and causing his top-line to deteriorate :( there are no professional saddle fitters anywhere near my area so I contacted Dover saddlery. They told me that they have a saddle fitter and he e-mailed me a list of measurements to take with a flexible ruler and then trace it on a paper. I send these tracing along with pictures to Dover and they will tell me what type/size(wide, narrow, etc) would fit him best. has anyone done this or does it seem legit? I don't want to do this and then buy a saddle that doesn't fit...does it seem too sketch to go about doing this? Thank you!