I stopped using it, when I found that some Sony 50p material contains GOP structures that are unexpected to MkvMerge, a tool I use to merge chapters and styled subtitles into .mkv files. The result was that the frame times got messed up in SVRT regions of the output and the video stuttered badly.
In addition SVRT is disable for many reasons. It requires a clean section of the original video and audio, starts at the first key frame, and doesn't mix with material of different quality (bit rate, FPS). So the gain diminishes as we add white balance, clips from other cameras with a different FPS, cross-fades or even just music.
What I need to do
My graphics card and many TVs only accelerate H.264 up to level 4.1. That means my 50p production wont play at all, or have frame drops or a/v synchronization issues. So I decided to go with 25i (e.g. 25 FPS, but 50 fields per second), which is available at level 4.1.
Using adaptive interlacing technology like MBAFF, interlacing will only occur in frames or parts of frames with motion while e.g. titles will be encoded progressively. Now with PD12's encoder even at high bit rates, I got some flickering issues and I like to have more control over my encoding. So I plan to use PD12 to create lossless YUV420 video (50p) (in whatever codec) and then then free ffmpeg and x264 codec to reinterlace and encode, which results in a stable picture.
You should not encode interlaced
If I want to view it on most hardware decoders, I need to have level 4.1 at most. That means either downscale to 1280x720 or reduce the frame rate to 25. Since all video clips used in the video is 1080p and many TV screens are 1080p, I think that's a bad option quality wise. 25p on the other hand feels less fluid and it is even hard to visually track small objects. (I already complain about action movies in 24p!

I do have bad memories of interlaced material looking really bad, but now we have hardware decoders with deinterlacers and to my surprise low motion Kent-Burns effects over photos looked the same in 25i and 50p. On the other hand 25p gave a slight stop-motion feel to them. (The video was interlaced with ffmpeg and x264.)
Lossless encodes in PD12?
So I found one lossless encoder in PD12. That is QuickTime, in "raw" mode. But that one outputs RGB and I would prefer to stay in the correct color space to avoid banding artifacts. Also the file size would be prohibitive compared to e.g. Lagarith. Next I tried hacking my profile.ini, where custom encoding profiles are stored, but I couldn't find a way to write lossless H.264 with PD12's encoder. So is it at all possible to output lossless YUV4:2:0 in PD to so the final encode with an external encoder?