Thought I would resurrect this thread in case others have a similar question. I worked with Jeff and obtained one of his well-made swing away adapters to try. Once I had it in I hand, I noticed two problems (to be clear: neither are Jeff's fault)- one, the design of the port is such that a lateral swing away holder puts the wet lens off the glass by about a cm. I would imagine optical performance suffers by having that much water between the glass surfaces. Two, the holder was just a little too large as this was the closest one Jeff had, and not a unit designed for this port. I filed away some of the material between the clamping surfaces and added some washers to the fixing bolt, and now it fits.
I haven't had a lot of opportunities to dive with the combination, but I did test it out in a tub along with a dome for the 12-40 (new thread coming soon for those of us with Oly OMD housings). The 12-40 does seem to work optically with the Olympus PTMC-01 macro lens, although the magnification gains weren't significant. I also tested the port and macro set-up with the 60 macro- it also works, and the gains there are more pronounced.
At the end of the day, I'm not sure if it's worth it to use with my Oly wet lens, especially since the dome I tested is probably going to end up on the housing most of the time. The Pro lens is sharp enough to withstand some heaving cropping- I'm including an example from earlier this year with a nudibranch that was less than 2-inches in length.
