Take the base cooldown and write is as "number of cooldowns per minute." (or hour or day or whatever, the specific unit doesn't matter, as long as it's consistent) Multiply it by your CDR percent as a decimal added to 1.
Example: Explosive Blast has a 6 second cooldown, which would be ten cooldowns per minute. You have 100% CDR, which we'll express as 1, and add it to 1, giving us 2. Multiply the number of cooldowns per minute by this number, to get 20. Now we can divide 60 seconds by 20 to get 3 seconds, the new cooldown.
If you had, say, 35% CDR, Explosive Blast's cooldown would be reduced to about 4.4 seconds. 1000% CDR would reduce it to about half a second.
TL;DR: Don't think of it as a percent decrease to your cooldowns, because that would allow you to remove your cooldowns entirely. Think of it as a percentage increase to how many times you can use an ability in a given timeframe. 50% CDR means you can use Explosive Blast (or whatever) 50% more times in the same timeframe than if you had 0% CDR.
Lore: all the wizard needs is something to channel the energy through. It could be a brick for all it matters, but wands, orbs, and staves are specially designed to enhance the arcane power as it ripples through them. A sword is just good for pointing and shooting lightning bolts and stuff.
Mechanics: wizard (and witch doctor) damage will actually keep scaling at the same rate as the "physical" classes, especially in inferno mode. All this means is "weapons = damage output." For everyone. Wiz and WD have specific weapons that they will prefer over everything else for the damage bonus, so there's no practical reason to carry a big 2H sword, because your damage output with it will be lower than with a wand and orb. Now I just wish they'd do this for the monk's skills that are still on scale-by-level.
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Example: Explosive Blast has a 6 second cooldown, which would be ten cooldowns per minute. You have 100% CDR, which we'll express as 1, and add it to 1, giving us 2. Multiply the number of cooldowns per minute by this number, to get 20. Now we can divide 60 seconds by 20 to get 3 seconds, the new cooldown.
If you had, say, 35% CDR, Explosive Blast's cooldown would be reduced to about 4.4 seconds. 1000% CDR would reduce it to about half a second.
TL;DR: Don't think of it as a percent decrease to your cooldowns, because that would allow you to remove your cooldowns entirely. Think of it as a percentage increase to how many times you can use an ability in a given timeframe. 50% CDR means you can use Explosive Blast (or whatever) 50% more times in the same timeframe than if you had 0% CDR.
1
Mechanics: wizard (and witch doctor) damage will actually keep scaling at the same rate as the "physical" classes, especially in inferno mode. All this means is "weapons = damage output." For everyone. Wiz and WD have specific weapons that they will prefer over everything else for the damage bonus, so there's no practical reason to carry a big 2H sword, because your damage output with it will be lower than with a wand and orb. Now I just wish they'd do this for the monk's skills that are still on scale-by-level.
Also, this:
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Interesting build, though. I can see how much control it gives you.