OBS! You cant revert Stag ability

[Tyze]

The "glyph" bought from Moonglade cannot be undone by vanishing powder as it should be.

Now im stuck with flight and stag form as a seperate ability.

[Nevcairiel]

Those are not "glyphs", they are actual additional spells you learn - not modifying another one. You can't unlearn any other spells once learned, can you?

[Nerxyrall]

the seperate stag form is the "people can mount me"-form, which was a glyph in wod.
Your travel form is still on one button. Go to a "no fly outdoor"-zone and test it.
My travel form (through glyph) is the gepard and so i can choose between stag and gepard whenever i want...

edit: or test it when you are in combat (much easier).

[huth]

Those books all just give you additional spells, they don't modify or remove existing ones. That's limited to Talents, Artifact Traits and Glyphs.