Something has happened to mineshaft generation between 1.11.1 and 1.11.2 and still exists in 1.11.3.

I was so pleased when mineshafts went back to generating like they did in the old days before they got super sized and very confused. However that only lasted 1 or 2 releases.

Now either mineshafts do not generate where /locate tells you they should be or they are so small they are very boring to explore and have only 1 or 2 chests if you are lucky e.g. The mine centre earth works used to have four, five or more exits. Now there may be two or three but one or two will be very short dead ends. This is also true in mesa biomes where I also came across a number of the mine centre earth works but no tunnels at all. The others that had generated were also very small.

Am I just unlucky or has something happened to mineshaft generation where it has completely flipped to the other side of the scale?