As I mentioned before you did this is "more than a dream" where the fact that the bit in D was major  was hinted at by having a Gmaj7 in there, giving an F# in the melody. You ve said that this is a very natural movement and it does sound as such, so have you used this same harmonic technique in any other songs of yours?
i'm not sure which thing you mean, but whether you are talking about slipping to minor-third-away sister keys, or landing in a new key on its 4maj7 with 3 note of new key in melody, both seem to occur quite frequently in my writing. again, in zero cases is this premeditated. the technique is to dive where i want to dive, and then let the analysts analyze later, which of course has no effect on the song, unless i notice certain maneuvers that are just happening way too often and then i try to avoid them for a while and find something new instead