Do alliance managers have to be two-faced?

I was sitting in an airport bar last week and struck up a conversation with the guy on the stool next two me. It turned out we both run the alliance teams for our particular companies, me in the PLM IT space, and him in the bio-medical space. After going through a few (very few) of the companies we both deal with and comiserating on howh ard it can be some times, he shared with me a key discovery he had made over the years. He had found that the key attribute of a successful alliance manager is to be two-faced. One face for the partner, one face for the company the manager works for.
He went on to explain that in order to move both parties along, there were certain pieces of information that it was valuable to ‘manage’ (withold, embellish…even in some cases fabricate!) to make the alliance move in the right direction. Sometimes the info was ‘managed’ to a partner and sometimes it was to the company the alliance manager worked for.
Although it was a casual conversation and we will likely never meet again (although we did trade cards…always build your network) the comment really stuck with me. I have been in situations where it might have been easier in the short term to ‘manage’ information. But I have yet to see a partner situation where information management is a viable long term strategy. Eventually it will either catch-up with you or you will waste so much time ‘managing’ information that you never get the value you want out of the alliance. I think partnerships in business are much like saving for retirement: small invenstments up front may be painful in the short term put pay big dividends in the long run. And since true alliances are always long term affairs, I think you have to establish an honest dialog right from the start. Save information management for databases and PDM systems.