A dot scope should be mounted as far forward as possible.  I strongly recommend investing in a gooseneck mount for it so that you can get it both further forward and lower towards the boreline.  On a gooseneck mount, you'll be able to set up the dot to cowitness with your iron sights, meaning you'll be able to use your irons through the optic if necessary.

-Troy

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Using the AimPoint normally, by looking over the irons.  The dot will usually be somewhat centered, but as long as you can see the dot on the target, you're gonna make hits.

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Using a conventional cheek weld, you can see that the dot lines up with the irons, proving that the dot is zeroed to the iron sights (this is called co-witnessing).  Note that if the dot were to fail, or if you had forgotten to turn it on, you could use your irons right through the AimPoint.  That's the advantage of co-witnessing.  Obviously, if the AimPoint was damaged to the point where you couldn't see through it, you could flip the ARMS lever and jettison the AimPoint, and your irons are good to go.

-Troy

I'm certainly no Billy Badass, but I have NO problem using my AimPoint mounted this way, nor do countless thousands of soldiers who have their AimPoints mounted at the same height (but with inferior mounts and with the AimPoint too far to the rear in most cases).

The higher your optic is, the narrower your elevation "sweet spot" is, and the greater the divergence is as range increases.  You only see the military using high-mounted reflex-type optics for one of two reasons:

1. Because they MUST be mounted higher to allow use with a gas mask, and
2. Because all they have are A2 (fixed carry handle) uppers, and they don't have the budget for gooseneck mounts.

As it is, my AimPoint's center is already a bit higher than the iron sights, allowing for more of a head's up view, and because the optic is mounted forward, you simply keep both eyes open and put your Dot Of Death on the target and squeeze the trigger.

Again, I'm no badass, but I'd be willing to bet that I'd be at least comparable to someone with a high-mounted AimPoint, if not faster, especially if the targets are at varying distances from 25-200m.

-Troy