It's pretty obvious you do not know what burst spec means dude.
Let me give you a few examples.
Fire mage is a burst spec:
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https://www.warcraftlogs.com/reports...done&source=43
Notice the massive spike, followed by a rapid decline and then bad damage until the next massive spike comes? That means the damage is loaded into CDs primarily, it is a burst spec.
Here's a moonkin:
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https://www.warcraftlogs.com/reports...done&source=46
Notice how the damage curve is a lot more even? That's because moonkin isn't primarily a burst spec. It has burst damage CDs, but it doesn't have as much of its damage loaded into a CD as a fire mage does.