What should be expected of marketing "experts?" Part VI

What does a seasoned marketing expert do when he finds out that a new "name brand" marketing expert will be brought on board above him?  And when it's rumored that the probable pay package for this "name" marketer (based on common knowledge of the candidate's current pay package where he works now) will be a stunning new high for the firm?  And when the firm has never hired a marketer as seasoned before? 

What expertise does this new guy have?  What might the senior management of this firm expect him to do (walk on water?)?   

I've watched this happen before.  Ms. or Mr. Big Name Marketer comes on board, and miracles are expected.  Usually a listening tour is undertaken, where Mr. Big Name flies all over the world to meet the heads of practices and regions. 

What's really happening is the beginning of the influence game.  These Big Names are perceived to have political savvy that can move all-too-intractable firm leaders, many of whom need a heavy hitter to convince them that investing in marketing is the right thing to do.  My question:  besides their tenure in marketing and previous big-name firm experience, do these Big Name Marketers have any formal credentials in what they are really being hired to do, which is arguably closer to politics than marketing?  Or do they just have an instinct and talent for sniffing out internal influencers, or a special flare at relationship building?  Can one get a degree in "relationship building?"

There's something wondrous about professional firms intentionally hiring who they perceive to be seasoned experts to influence the positive direction of marketing.  If done well, we can assume that Ms. Big Name's already-in-place team will have a better working environment for marketing -- and will enjoy the rewards of getting a kick-#$% marketing program underway.  But I wonder if everybody really acknowledges that their goal is to hire an Influencer, and if they are really looking at the right credentials to fill the bill. 

And I wonder how this situation affects the high turnover among senior marketers...