“Finding common preferences” and “solving problems non-coercively” have exactly the same denotation (meaning), but somewhat different connotations (suggested implications).
To illustrate this distinction, imagine answering the question “how many squares are there on a chess board?” One could reply “64” or “8x8” or “1000-936”. Each of these answers has the same denotation (they all indicate the correct number of squares), but a different connotation: “64” ... if you count them, that's what you'll get; “8x8” hints at an explanation as well as a literal answer, by referring to the board being an 8 by 8 square; 1000-936 is extremely confusing because it seems to imply that the difference between the number of squares and 1000 is important, which is false.
“Finding common preferences” may, for many people, carry the connotation of some sort of method, ritual, or process (such as sitting in a circle taking turns expressing feelings while everyone else is required to listen) but this is a mistake. On the other hand, “solving problems non-coercively” does not have such connotations. “Finding common preferences” and “solving problems non-coercively” are, in fact, the same thing. If you genuinely prefer a solution (it's a common preference) then you cannot be coerced by it: you are getting what you want. Moreover, all cases of coercion can be regarded as failures to find common preferences, because the coerced parties did not get to enact a solution that they preferred.