Using CARD to find CARs with roaming agreement with my ISP?

Hi!

Would it be feasible to use CARD to find out whether a CAR
is likely to give me Internet access (in advance of a handoff)?
The case I am interested in is when a customer is about to
perform a handoff and would like to know the set of CARs that
are either run by his/her ISP or by an ISP with a roaming
agreement with his/her ISP.

I was reading the draft "Issues in candidate access router
discovery for seamless IP-level handoffs", 
(draft-ietf-seamoby-cardiscovery-issues-04.txt)
but this case was not mentioned in list with sample scenarios
for CARD motivation.

BW J-O