So can the solid OEM fan blades, and as a matter of fact I have seen a lot more OEM's come apart than flexes.
Never seen a clutched fan disassemble at RPM's though, just the direct drives.
The one piece molded flex fans are stout. I always under drive them so they never get close to their 8000 RPM rating. I just replaced the fan clutch on my van Sunday because it actually locked up.
