ZFS sync / ZIL clarification

[Mark Felder]

Thanks Peter. You're also confirming my original suspicions and the  
results of my testing.

I'm going to continue forward with this ZFS SAN backend for ESXi project  
with iSCSI via istgt, which actually works surprisingly well.

Honestly, NFS would have been quite useful, but it never would have made  
sense in our environment because you can't properly multipath to it  
without pNFS / NFS 4.1, which isn't available in FreeBSD yet and will take  
some time to prove its stability anyway.