We're getting away from the OP question.
That's a good explanation on the link. Wilhelm used to repair scopes. He knows what he's talking about.
I think Andy has done the only adjustment possible on the VX-1 which is focussing the reticle. He will be used to focussing the target using a parallax knob too. Then both target and reticle are sharp at the same time. I suspect that if you're a bit short or long sighted the actual parallax movement might not be zeroed at the same time. For careful shots I try to zero out the parallax and then the target is not quite sharp, which is the least important of the three. The VX-1 is set to a compromise and I think a young shooter has better focussing ability specially up close so will be able to make better use of it. If you're over 50 and need reading glasses you start to notice imperfect focus and can't get round it. I doesn't help if you've also got a really good parallax adjustable scope to compare it to. VX-1 is a good scope for what its designed ad priced to do.
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