Here are a couple key words and phrases, I've incorporated into my vernacular. Hopefully, these will help out next time you are in an architecture/design session. (or a conversation with your significant other =)
"I appreciate X":
Always use the phrase, "I appreciate that..." in response to a point. But more importantly, *mean* it. It is an age-old adage, but when talking, it is best to listen. Once you've heard the other party, try to understand and appreciate what they are saying. Then, let them know that you appreciate their point, before adding additional information to the conversation. (tnx to +Jeff Klein for this one)
"I am not passionate about X"
To drive consensus, I try to hold focused design discussions. During those discussions, I'd try to squash tangential topics. I used to say, "I don't care about that, do whatever, we're focused on X". Obviously, that would aggravate the people that did care about X. These days, I use the phrase, "I am not passionate about that...". People have different value-systems. Those value systems drive different priorities. It is important to acknowledge that, while also keeping discussions focused. (tnx to +Bob Binion for this one)
"What is the motivation / thought process behind X?"
People enter meetings with different intentions. Those intentions often drive their positions. It is tremendously important to understand those motivations, especially in larger companies or B2B interactions where organizational dynamics come into play. In those contexts, success is often gauged by the size of one's department. Thus, suggesting an approach that eliminates departments of people is a difficult conversation. Sometimes you don't have the right people in the room for that conversation. I've found that it is often useful to tease out motivations and the thought processes behind positions. Then you can address them directly, or at least "appreciate"=) that motivations are in conflict.
Eliminate the "But's"
This is a simple change, but a monumental difference in both diction and philosophy. If you listen to *yourself*, you'll likely make statements like, "X is great, but consider Y". You'll be surprised how many of these can actually be changed to, "X is great, *and* consider Y". Believe me, this changes the whole dynamic of the conversation.
AND, this actually begins to change the way you think...
When you view the world as a set of boolean tradeoffs, "either you can have X or you can have Y", you never consider the potential of having X *and* Y. Considering that possibility is at the root of many innovations. (e.g. I want multi-dimensional analytics AND I want them in real-time!)
F. Scott Fitzgerald said, "The test of a first-rate intelligence is the ability to hold two opposed ideas in the mind at the same time, and still retain the ability to function." These days, this is how I try to live my life, embracing the "what if?" and then delivering on it. =)