I have a titan fenrir cooler. What I did is take 600, 800, 1000, 1500, and then 2000 grit sandpaper. Then place sandpaper on flat surface(preferably locked down on both ends) and took the cooler with no pressure applied, just weight of cooler, and went up and down 10 times then turned cooler 90 degrees, 10 more etc... all the way around on each grade of sandpaper. (wet sandpaper and apply dishwashing liquid(1 drop) on paper each turn). At 2000 grit, Grooves were slightly visible but not feelable to the touch. Clean mounting surface with alcohol. Then use credit card to apply very thin film of paste on cooler base. Then used grain of rice method on cpu itself. Can run prime for 8hrs on I7-950 with 1.216vcore @4.0ghz with temps max core reaches 68degrees celcius. This dropped from 76 degrees before. Using artic silver 5 paste.
I imagine if someone did this with noctua dh-14. The results would be even more astounding than what I have. Direct cu pipes or not. If you spend money on something, you can make that cooler base better with a little time and patience. Better surface equals better heat transfer and better temps, which of course equals higher GHZ!!!
