Handling of -all

I think we're all aware that SPF does not work well with message 
forwarding (college alumni addresses and the like).  Given that's the 
case, how should -all be handled?  Two possibilities I can think of:
(1) Originating domains that potentially send through forwarders should 
not publish a -all policy, since some recipients might inappropriately 
reject forwarded messages.  Since it's hard to know what addresses are 
forwarded, -all policies would probably be quite rare.
(2) SPF verifiers should not reject mail that does not match a -all 
policy, because of the possibility it came through a forwarder.
In other words, should the domain publish a gentler policy to allow for 
forwarders or should recipients apply a gentler response?
-Jim