The tnat tool is quite clever. I previously ran a IPv6 only infrastructure and it worked really well, except for some "old" applications written in C which only handled IPv4. Which I had known of this hack.
It's a great tool for sure. I've tried to find approach to patch naughty IPv4 only apps with my own LD_PRELOAD library and during research phase I found tnat64 and it worked exactly as I expected.