It’s always up to the operator to determine which configuration works best for him, but with the reliance on battery operatored optics and high mounted optics, it’s really a good idea for a user to consider the what ifs. What do you do with your Eotech if the batteries die? What happens if the optics come loose ? Scope mounts can come loose and even break, I’ve seen this happen on M1A rifles, AK, FAL and AR15s on several ocassions. Sometimes its a good idea to train yourself to be able to hit a target without even a rear sight. There have been several times where I actually forgot to flip up my rear sights on my co-witness configuration and just used the sight picture from my Eotech optic and the front sight post. I never missed what I was aiming at and it was actually good practice for me.
If you can get a good cheek weld, and you know approx. where your poi is, you should be able to hit a man size target out several hundred yards with just a front sight post. I’m sure you’ll burn through a few more rounds to hit your target, but it is possible. Many Trijicon ACOG rifle scopes are being used with red dots mounted on the top or have iron sights mounted on the top of the scope. The TA01 NSN seems to be the popular configuration I am seeing around. This will give you fast transition from CQB or long range engagements, It also gives you more than one targeting system incase one goes down.