Hi George,
I agree with Dave and urmas.
I usually use (Administration -->Groups--> Go to a group -->on the Resource Tab add a resource).
When I add resource1, resource2 and resource3 to group1, I will have to access 3 resources properties page 3 times.
When I add group1 to resource1, resource2, resource3, I will only access group1 properties 1 time.
I will choose a direction with few work loads.
So, when I grant group access right to multiple resources, I will use (Administration -->Groups--> Go to a group -->on the Resource Tab add a resource).
If there are many resources, I may use XOG.
Regards,
Shoichi