Not sure of exact year, but suspect it was when they started irrigating greens in any fashion. I have seen irrigation plans as early as 1916, and I bet they sold like pet rocks in their initial offerings (high tech stocks? I don't know, trying to be funny w/o coffee this morning.....)
And, I'm in the "never was" camp over the "has been" regarding the B. Especially for a long par 3. Yes you can offer a few multiple tees so all player are hitting fw wood or driver, and those clubs didn't fly as high as they do now. But even back then, on any of those tees, a large percentage of golfers would be in between clubs to make that shot work, no?
That said, I have built four over 35 years -Two on long par 3's, one each on short par 4, and a short par 5. I tend to think that the wild contours and divided green works better for short driveable par 4 holes or reachable par 5 holes these days, but the club selection issue is similar in any era. But, as noted, when the pin is front or back, at least you can hit the high fliger to a smaller target with bigger putting consequences for missing. I don't think a sub divided green for a 250+ shot these days is necessarily good design (i.e., would expect many players to think it "unfair," too much of a penalty for a long approach, or at least beyond their abilities to execute consistently.
And, as mentioned, the short, Eden, Redan, triple plateau and a few other MacRaynor greens have stood up pretty well as concepts.
If any green concept raises my suspicion that we shouldn't just revere the old guys as having done no wrong more than most other features. As a corollary, it has always made me question whether every old green is worth restoring. I mean, if Raynor decided on the same 18 greens over and over, it is unlikely that the design was a case of "form follows function" then, and even less so now, given how the game has changed.