All I can say is, that it works even on a Synology, it works on Windows (ofc), it works on EMC SANs, on IBM SANs, on Purestorage SANs and on Nimble SANs and probably on many more platforms. AFAIK they are all Unix based and many of them also hyper fast (you stating stuff getting slow if having to choose paths). In 20 years of Enterprise IT this is the first system I encounter which doesn't allow this.
Show us the RFCs which prohibit this, maybe you're reading them wrong.