Quote Originally Posted by 'Souca',index.php?page=Thread&postID=177848#post17 7848
Glyph of Horn of Winter is actually very bad now. Not sure if it was fixed in 3.0.9, but in 3.0.8 if someone with the glyph had cast HoW, unglyphed players would not be able to cast it as there was a "more powerful spell active". This might not matter if all 5 have the glyph, but it gives no benefit except saving a GCD every 2 minutes.
Last I checked, it still does that. However, if you add /cancelaura Horn of Winter to your macro just before casting it, you will remove the buff and not get the error that says you already have a more powerful spell active. Hope that helps.