… doubt that Yosemite corrupts a disk …
		
		
	 
+1
	
		
	
	
		
		
			If you search the forums for disk errors occurring after the loading of Yosemite you will find quite a few.  Either we all have disk problems or Yosemite is a super diagnostic tool for uncovering them. …
		
		
	 
With respect: it's far more complex (and frustrating) than either/or. 
Recently, in a topic unrelated to storage I wrote: 
	
	
		
		
			… Around the times of past upgrades to the OS, pre-release and in the days following release, I quietly but very closely observed public fora. (Detailed reasons for me doing so are off-topic; essentially it was to bring an experienced response to recognisably difficult or misinterpreted problems … 
		
		
	 
Those contributions from me, typically in Apple Support Communities, were fairly often in storage-oriented topics – Disk Utility, fsck_hfs, HFS Plus, Core Storage, fsck_cs and so on – where many "me too" responses were inappropriate (whatever problem was in the opening post, those "me too" replies were from people whose problems were different); where people wrongly imagined that problems with storage following an installation were due to a bug in the installation package; and so on. 
Without going into detail, I became focused on the (then) fitness for purpose of things such as HFS Plus, fsck_hfs and (most noticeably) Disk Utility. A frustratingly huge amount of time can be wasted by individual customers, and by groups of customers, as a result of the combined inadequacies of those three things. After long and careful consideration: 
https://alpha.app.net/grahamperrin/post/23338278 and what happened next is probably overwhelmingly, painfully obvious but for those of you who haven't noticed: not only does the 
latest OS X have what's almost certainly a 
legacy file system (Mac OS 
Extended Overextended), it also has, for me and a few others, the 
worst-looking interface ever inflicted on a Mac. 
With apologies (again) to Al: that combination of 'legacy + worst' is not an incentive, from Apple, for me to offer storage-related advice where that advice is most 
urgently required/desired by a few customers. For the greater 
long-term good, I find it necessary to focus my efforts on the problems with appearance. 
Still, I'll occasionally dip into topics such as this … good luck, y'all.