Originally Posted by
Recom
If glyphing FE allows you to have a higher uptime then do so. For example a 4 min fight, without the glyph you can use FET once and it's gonna be up for 1 min, with the glyph you can drop it twice for a total of 72 sec so it's a slight gain. If there is a burst mechanic like Wind Lord Meljarak HM, using the glyph can be an increase. And lastly, using the glyph in combination with PE can be an increase (would have to sim to be sure).
I didn't tinker a lot with AS so I can't say.