I would say yes this is still a requirement on the Windows side. If you write disk signatures or format the drives in windows the ESX will no longer be able to use the drives and you will have just lost any / all data on that LUN.
As for a whitepaper or howto guide on making the LUNs available to the windows machine, I would suggest getting in touch with your SAN provider. They should be able to walk you through setting this up. Just make sure that when the LUNs are presented and you see them in Windows disk manager they are marked as Online, otherwise you may have problems removing the snapshots after the backups are completed.