Why is there no solid answers on SR oil restrictors?

[NukeKS14]

"An oil restrictor is recommended for optimal performance with ball bearing turbochargers. Oil pressure of 40 ? 45 psi at maximum engine speed is recommended to prevent damage to the turbocharger?s internals. In order to achieve this pressure, a restrictor with a 0.040? orifice will normally suffice, but you should always verify the oil pressure entering the turbo after the restrictor in ensuring that the components are functioning properly. Recommended oil feed is -3AN or -4AN line or hose/tubing with a similar ID. As always, use an oil filter that meets or exceeds the OEM specifications.

OIL LEAKAGE SHOULD NOT OCCUR ON A PROPERLY FUNCTIONING SYSTEM IF RESTRICTOR IS NOT USED UNLESS THE SYSTEM PRESSURE IS EXCESSIVELY HIGH."

Straight from the mfr. Why don't people think to look to the company that manufactured their parts for recommendations and specifications for proper operation? And it isn't different on every individual turbo. Garrett manufactures their turbos to a general set of operating conditions for cooling and oiling.

So, as always, it depends. The oil pressure is key here. Can you run a bb turbo with no restrictor? sure. If your oil pressure is below 40-45 psi. What size of feed line are you running? what side of drain line? if there is a restriction in the drain, the pressure the turbo will see increases. There isn't a blanket yes/no answer.

Example, I see about 65 psi oil pressure when my engine is cold at cruising rpms (3.5K ish) but when the motor heats up that'll go down to 55-57 as taken at the oil filter block. I need a cooler setup but, with a -4AN line and appropriately sized adapter on my BW journal bearing turbo, I have no issues.

TL;DR - it depends, but, measure your oil pressure at the feed line. .060" may be too large if pressure on the turbo side is exceeding 40-45psi peak (I read drift so, I'm guessing that's a yes.)

Also in for people who operated outside of this just fine. That'll happen too. This is just Garrett's recommendation, not absolute law.