GTR stopped installing tips because of "one customer"! The guy kept sending in ivory tip-ends that were too small for the knives he wanted made. The shop finally received a tip that was close in size and made one of the knives he wanted. Upon receipt, the customer complained that the tip wasn't "right" and accused the shop of "switching" his ivory with another piece!
That was it! ...about 15 years ago! Hope this helps.
Best, Capt. Chris