"This thing that you're always going to have is arguably better than this other thing you're always going to have. To find out why you should care, read some other post that has nothing to do with the topic at hand."
How is this useful, exactly?
Killars also swapped out the tricks glyph for the feint glyph. On fights where you are using feint constantly, you could save more energy with this glyph than with the tricks glyph. Feint costs 20 energy and 0 when glyphed where as tricks costs 15 energy and 0 when glyphed (and -5% damage). If you find yourself using feint every 30 -40 seconds or less, then you would gain more energy during that fight with a free feint than a free tricks. I am not sure Shadowcraft has a way to model DPS change from the energy gained when using the Feint glyph.
As to why not have both the feint and tricks glyph for the fight where you need to use feint a lot, I'd refer to Naihan's response above.