Linux LVM knows nothing about the alternate path to your PV. If you extend your volume group to the alternate PV, LVM treats the alt device as if it were a new PV.
When the system starts up, it calls vgscan to scan all the devices; and I don't know what lvm2 does when it finds lvm2 VGDA on the alternate PVs. Perhaps, it just ignores it.
With the Demise of Sistina, looks like the official stance is to advise mdadm etc. Neverthless, that also is kind of incomplete, as mdadm has on-disk metadata and modifies it and hence is NOT cluster-safe for concurrent activation.
Not sure about EVMs, whether it supports alternate PV links. More on that later...
Drop a comment if you have something to say on Linux LVM.