Besides greater probablity of discovery, are there other **significant** optimizations a of mining pool? Besides the benefit of increased attempts, are there any other significant, measurable optimizations that mining pools provide? I'm referring to intrinsic functions such as non-duplication of failed "hashes" (assuming this is actually an implemented feature) that is a direct yield of mining hardware/software working in concert, not mining farm benefits such as economies of scale savings (i.e. group discounts on energy).
Yes. 

Usually if you would solo-mine you will need to update/download the entire blockchain, which as of right now, is 141GB.

If you join a pool, this isn't the case, You actually don't even need to be connected to any of the peers/nodes from the bitcoin network. 

This could greatly decrease the money you would spend on bandwith in some countries, which could be another reason to join Pool-mining.

It also saves you a lot of time, depending on your internet speed.