(!empty($user->lang['QUOTE'])) ? $user->lang['QUOTE'] : ucwords(strtolower(str_replace('_', ' ', 'QUOTE'))):
You don't need a lot of mana if you kill everything on the second blizzard, you just need a lot of +damage gear like I have.
If wear +frost spell gear while you're AoE grinding, you are a !@#$%^&*. AoE spells barely make use or spell power, unlike single cast spells such as frostbolt.
Example: If you have 150 frost spell damage. You frostbolt with hit for arround 150 more. If you cast Cone of Cold on ONE mob, it will hit for like 5 more damage, insead of 150.
The correct gear to use for AoE grinding is INT. Not Eagle, Owl, Stamina, +frost, or anything else. Once you know what you're doing, the mobs will do little or no damage to you at all.
To the OP:
I'm going to rewrite my own version of this guide. This guide is very unrealistic, and would require you to use a mana ruby and mana pot each time you do it.
First, you do not use mana shield. You use Ice Barrier. Ice barrier absorbs more damage, and doesnt use your mana when you take damage.
Second, no level 50 mage has enough mana to cast all the spells you suggest.
Blizzard x 4 = 3200 mana each cast (15% reduction in cost of frost spells from talent)
Mana shield = 880 (100 to cast, 780 for absorbsion)
Blink X 2 = 700 (I don't know exactl how much Blink costs at level 50, it is about 425 at level 60. I just chose 350 mana at level 50 in estimation)
CoC x 2 = 650 (323 mana each, with 15% reduction in frost spells)
Grand Total of = 5430 mana per kite. The only way anyone would ever get this much mana at level 50, is if they had ALL max level int gear, gnomish racial, the 8% increase in mana from arcane, and full raid buffs.