"In dealing with institutional customers, I even take it a step further. Before I invest any time in the sales cycle, I have them teach me what it takes to get a sale, exactly what I have to do, and how long it will take. Real buyers will be happy to tell you all of this; in fact, they may think you're amateurs if you don't bother to ask. Lots of times the buyer may be frustrated be their own organization and will coach you to be more successful so that they can get what they want."
I think this is extremely important not only with institutional customers, but with the general public as well. Every different market segment is going to have it's own rules about how they buy, who they buy from, how trust is built, how long it will take, what hoops you have to jump through in order to get them to take out their wallets. Then once the wallets are out, there is a whole other aspect to getting them to commit.
Like you said, people won't take you seriously if you don't know how to play the rules of the game.