Почему сомнительно? Помнится, в одной довольно обстоятельной русскоязычной статье о Ф-119 эта технология называлась прогрессивной и ставилась ему в плюс.
The F-119 has a three stage fan, a six stage compressor and single stage low and high pressure turbines. Throughout the fan and compressor, the disks and blades are one-piece components. The large, hollow Titanium first-stage blades are made separately and then joined to the disk by friction wielding, a technique in which the blade is rubbed so hard against the disk that it bonds together.