In think that one of the most valuable traits of an enterprise architect is the ability to push gently.  In other words, if you find that a team is developing a solution that cannot be integrated or creates an entirely new definition for the word, customer, you recognize that this is a negative for the business, but you don’t wave your arms and scream… you push gently, but firmly, on the people who made that decision to ‘unmake’ it within the scope of the planned iterations.

You can go live with a wrong thing if it is on the plan to go live with the right thing in the next release.