Maybe you need to read the description of both skills, and if you don't see a diffrence maybe try actually using them...
MMk: SQ requires ranger secondary, has a 45 second recharge. Glyph of swiftness allows you to go into mesmer for mantra of resolve or earth (for stone striker), and has a 20 second recharge. You dont need glyph of elemental power because OF with a 20% weapon and glyph will last 100% of the time, without "waiting".