User blog comment:Blackendedsoul/The Authority of Admirals/@comment-3563898-20130706085026/@comment-6920514-20130709015522

To add to DP's point I remember DD offering Crocodile to work for him in the presence of the marines after he had just escaped from Impel Down. Being an underling seems to be an easy work around for the Warlords getting high bounty crew members but they don't want alliance because that would imply that they stand on equal footing. Warlords priveleges can't appear to be shared only to rule over their crews nor their decisions swayed by non-WG sanctioned pirates.