The Ozment writing system

One of the things I've learned about penwork is the role muscle memory plays in crafting the letters.  That's why when I practice I try really hard to do it the right way--warming up first, making sure my posture is good, making sure I am using the large muscles of my arm and not wiggling my wrist as in normal writing, etc.   Seems someone back in the day dreamed up a way to help people get that  motion down with a series of cards embossed with the correct forms of Spencerian letters.   Included was a stylus to trace the grooves.   I haven't tried Spencerian yet though I'm interested.   If and when I do, this may help.