well , this is an interesting perspective I never thought of , don’t really buy it , but interesting none the less …https://io9.gizmodo.com/this-theory-shows-why-c-3po-is-the-secret-hero-of-star-1829149241
I think there’s evidence for this theory in the original movie, but after that he was written to be much more bumbling and less crafty.
I assume that’s because he was initially written as an oily used-car salesman type character, but Lucas finally conceded to Tony Daniels’ take on things. I like Threepio. He had some nice moments in TESB too, but I think he’s gotten a raw deal ever since. Daniels seems to be doing an impression of Threepio these days, rather than just being Threepio. He was (comparatively) edgier in the first two films I think.