out of curiosity, are you aware of something in the rules that states that you are allowed to do this? or are you surmising that it is true because it is not specifically disallowed? (not disagreeing with you just curious as to your reasoning!)
First, I am going to turn this back around on you and ask you the inverse question, why do you believe replacing the thrown disc is not allowed? What can you point to in the rules that says this? Is there some general reason why you think it is illegal? I have a good idea why you think this, but I'd like to hear what you have to say first.
To the best of my recollection, I first came across the idea that this was allowed in watching tournament coverage. I believe I have seen players do it, and I am pretty sure I've heard commentators reference the idea. But, I can't point to any specific video.
I also seem to recall it being mentioned multiple times here by those who should know, perhaps by krupicka, but maybe by someone else that I thought I could trust to be correct on this issue. But again, I can't point to a specific comment.
But, the basic idea does arise out of multiple situations where it's clear that you can create your lie multiple times and everything is fine so long as the lie you create is legal. For instance, if drop a marker for your disc and decide it is not in the right place, you simply place it again in the right spot. If you had gone OB and dropped your marker disc in a legal place, but not the place you actually intended, you could move it wherever you wanted along the legal arc created by the rule instantiated this year. If you were taking optional relief and dropped your marker, but then decided to move it to some other point along the line of play, you would be entitled to do so. If you decided to rethrow, you could recreate your original lie as best as possible subject to challenge by the card.
The only mandate in the rules is that your marker be in a legal spot when you execute your throw. When marking your lie in accordance with the rules, you are entitled to place it precisely as you wish in any legal location. The range of legal locations is determined by where your disc comes to rest, but this doesn't mean that when taking the opportunity to mark you give up the right to move the mark to some other location that was legally determined by the position your disc came to rest in.