Referencing this page:
I've loved this guide and have been following it pretty religiously. I recently decided to check "finish leveling inscription" off of my WotLK bucket list and went to work herbing up a storm in Hellfire.
I got my ~60 Silvery pigment and started making inks... which put me at the cap of 255. Problem is, none of the glyphs listed for 254-260 are orange after 255, including those that can't be trained until 255--you train them at yellow, they're never orange at all.
Even if you stop making ink when you get 254, you only get one orange glyph to take you to 257, leaving you spending NINE inks to get to 260. In my case, starting at 255, I had to spend 15 inks to get to 260 (5 glyphs, 3 per glyph).
Hindsight being 20/20, I realize now that scrolls only cost one ink. It'd be worth tweaking the guide to explicitly tell people not to make ink past 254 in order to get the free three-fer skillup, to make scrolls from 255-260, and/or to gather more pigment to compensate for needing more ink (unnecessary if you go 254->257 and then make three Scrolls of Spirit V, which are the only orange ones at that level).
Thanks for the guide, it's been fantastic besides this speedbump. Off to rip more plants out of the ground in Hellfire now.