Do you have any reputable data at all to back up that claim? I've found fan failure to be a major source of drive and enclosure failure.
What? Well, heat = failure for hard drives. This is common sense. So if the fan fails, then I guess the drive would overheat and fail.
Any hard drive needs to operate at a proper temp. This goes for a drive inside your case as well as an external drive. A fan cooling the hard drive will keep it at an appropriate operating temp so it will not fail, and is pretty much a requirement if you are going to use a drive for heavy reading/writing on a daily basis.
And the fan in a Glyph enclosure is not going to fail, btw. Glyph hard drives are the industry standard for both audio production and video. They are the only firewire drives officially certified for use by Pro Tools, and are used in every major studio in the US. This is not some cheap little external enclosure from wal-mart.
Here is the blurb from Pro Tools:
http://www.digidesign.com/index.cfm?navid=54&itemid=23114
"Please Note:
* Hard drives using the Oxford 924 chipset interface have FW800, FW400, USB 2.0, and eSATA ports on them. (In our testing, Digidesign qualified Glyph GT Series Hard Drives with the Oxford 924 chipset)"
Or read on the Glyph website for more info about their drives.