In ancient times there was no limit how big amp you could put on a gun - A106 on Opalo was OK.
To end this practice and balance the game a new rule was made - weapon can effectively use an amp no bigger than half of it's max damage.

When tiering was introduced this old rule was forgotten. Now you can actually rise your weapons maximum damage, but the rule still calculates the limit using the old system. So did i increase the damage on my gun, or i didn't increase?
Does not make sense.

If there's a question about balancing, well, make the damage enhancers break more often on the amped gun or something.