To me it all comes down to perspective, and trying to understand where someone is coming from when they make a statement, and figuring out what they're trying to address.
Perhaps one teacher tells you to "stand up straight" on your own axis, while another tells you to be "more forward." Do these concepts contradict each other? It could seem that way. But in what context did each make the statement? Was one teaching an on-axis style, while the other was teaching a shared axis? Was one said at the beginning of your tango journey (when, perhaps, you were falling back or pulling your center away too soon) and the other a bit later on when an existing technique was being refined and tweaked? For that matter, were they even addressing the same issue--"stand up straight" could refer to not collapsing your center and, instead, having good posture, while "more forward" seems to be more a description of where over your feet to be centered. For me, context is the first issue to consider.
Along with that, I try to determine what is purely a stylistic difference versus what is a technique difference designed for different/better results. I do this by asking questions. "You're telling me to walk with toe leads. Previously I've had heel leads stressed. What is the difference you see? What is the benefit to walking one way versus another?" Whenever I've done this, I've always found teachers very willing to either describe what they see as the benefits of their particular method, or to discuss that it's a personal preference.
If there are what seem to be legit reasons for the technique differences, I think about how it fits in with other things I've been told that seem to be contradictory. Perhaps one thing was said and meant with a narrow application, perhaps it was an exception, whereas the other statement was more general. I ask myself if I'm getting two sides of the same coin. I ponder if it is merely two different teachers' ways of expressing themselves, because all teachers are going to describe things a bit differently. If it's a statement that I've heard from someone else, particularly in the context of their own lesson (such as here on D-F), I try to understand how that relates to me...if at all. (This sort of goes back to my first point--the teacher could be correcting a problem specific to another student.)
And, also, I think about the different statements and try them each out, and figure out what works for me. Perhaps one technique is easier than another because of something with my own dancing.
*shrug*