What is the core argument you're making here? I mean sure, I too can argue any point by making up examples about abstract projects A and B, but I'm not seeing what fundamental dynamic you're trying to illustrate here.
There's no argument; as I said, I'm sharing a perspective. Most engineers, and you can see it in the comments here, approach estimation as an us vs. them battle of wills. The perception battle that they deal with on a regular basis isn't going to improve that way.