All this seems counter-intuitive to me. The strings should be the tool of the player to achieve the best performance on court:
1) more wins
2) fewest UE's
3) most consisitency
4) most control
The string matters, and you can't just pick any ol' string and just "go with it". Changing a setup drastically could mean twice as many unforced errors, which translates into more losses.
If longevity is the only concern, then yes, one can find very resilient string that can last for dozens of hours of play time. But at what cost?
If your current setup gets you where you want to go, gets you the wins you need, the control you need, then if you change to a more resilient string, you may see other aspects of your game suffer.
This is why pro players use the strings that they do. Yes, they last only a couple of hours. Yes, it requires frequent re-stringing (didn't Serena re-string around 75 times in one of the Masters tournaments this year?), but it gets them wins and it gives them confidence.
Find the string that lets you do exactly what you WANT to do on the court, and you'll find your "magic bullet". If you've found that string, then great: keep using it. I know you play for hundreds of hours, but so what? What good is it to practice the right strokes with the wrong string? All you're doing is training your muscle memory to remember the wrong result.
If you turn around and play an "important match" and then switch to whatever is your "high performance" strings, then how are your muscles going to switch gears? You've just logged hundreds of hours with the wrong string, with your shots landing in areas where they normally wouldn't with better string.
Just my hypothetical 0.02.