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Glyph of Chaining was another one of those oddball situational major glyphs given to Resto Shamans. It would increase the jump of Chain Heal by 100% but added an annoying 4 second cooldown to the spell.
5.4 will see that Glyph of Chaining CD reduced from 4 seconds to 2 seconds. It might make it a bit more appealing for Shamans for situational fights and would probably be worth it for a Shaman to buy the glyph to have it when that oddball situation arises.
