Every piece of equipment needs to be inspected before you use it. I can't think of any that I have that don't mention this in the documentation, but it's certainly mentioned on here a lot and elsewhere. The OmniBlock is no different.
I usually inspect my stuff as I'm putting it away, so I don't worry so much about it when I start a job, but it needs to be done, at one end of the job or the other. These blocks are rebuildable. If you want to be able to replace worn out parts on an expensive tool, there has to be a way to take it apart, and you need to keep an eye on it to make sure none of it gets loose.
I'm rather amazed at how people will complain about throwaway products that can't be repaired, but think a well made product that
can be repaired is defective, somehow, if parts designed to be removable come loose with constant use and abuse. These are great pulleys... the complexity of making them rebuildable and midline attachable means you have to inspect them more often and tighten up anything that gets loose.
Of course, if you don't ever read the documentation, you won't notice that this is actually mentioned in there.