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I couldn't imagine why, the end result is the same either way. I am not sure I would be so quick to call any lower or RE defective if this problem were to present itself. I would attribute it to tolerance stacking.
I can't imagine that the thread roller or tap is engaging every RE and every lower at the same place every time on every piece at every manufacturer. So there are going to be some differences in where the threads start which will result in slight differences and once in a blue moon, a problem like this.
If this level of quality control like this existed in firearms, screws would be tightened by the number of turns and not torque.
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I think you'll be okay with it. Just check it out frequently after you fire.