I get very frustrated when people fail to understand what I'm saying, as my thoughts are pretty much the only thing I'm attached to. Once understanding is reached, though, all is well. So long as everyone is communicating, I'm dandy.
The ramification of weak Fi, the best I can tell, is that I'm just not motivated by my feelings in any significant way. I've little concept of how I might personally be affected by things, and I have trouble seeing why it should matter. Often I can't tell if I like or dislike a thing. So long as it doesn't interrupt my train of thought, and doesn't generate any particularly interesting new thoughts, I tend to be profoundly impartial. I have trouble recognizing what mood I'm in, and rarely think of taking it into account. Because, you know, why? That's just me.
My last partner seemed to assume if I expressed a preference, it was an absolute decree: I will accept this, and only this. Generally, though, uh, no. If red is important to you, by all means go with the red. I'm just saying a contrast would be more interesting. Why are you angry?
If something is important, I'll explain it in detail, so you understand the rationale behind it. If I don't do that, chances are I don't really care.