Optics, Mounts, and BUIS?

[JW1069]

Simple question? Do you actually try to line the dot up with your irons when shooting? If so, your going at this all wrong.

I should clarify a bit - my vision isn't 20/20 and there are times when my eye will blur the aperature opening and foul my sight picture for a moment. A blink or two usually corrects this problem. I kept the rear fixed BUIS on my 15-22 to help train through the issue, but there's no question that for me I shoot the RDS optics faster without a fixed rear BUIS in the way.

[Failure2Stop]

Is the nature of a red dot sight that it should be zeroed even if the dot is not perfectly in the center of the lens? If that's the case then I guess I have a fundamental misunderstanding of how RDS's work.

I ask because it always baffled me how an Eotech would still be useful even with part of the window destroyed or obscured.

It will be very close to being zeroed.
With any optic there is parallax, though for practical purposes the amount of parallax induced by being off center with an Eo or AP is minimal.
That is a big part of what makes them so valuable for gunfighting application.

Of course, the more centered the dot is in the window, the more consistent you will be, which is particularly pertinent to precision and zeroing.

This is what permits a lower 1/3 cowitness, which allows the user to keep the irons deployed (or use a fixed BUIS) but use the dot, and then simply slide into the irons if the dot isn't working.