This thread inspired me a little to try making reversal photographs straight out of the camera.
However, my approach has been to employ the Sabbatier effect onto a contrasty and medium dense paper negative.
This results in a positive with a good range of tones and fair crispness, but it definitely constrains overall contrast.
I definitely haven't mastered this technique at all, but I have made a few nice looking images fooling around.
This is a self portrait that I reversed, scanned, and photoshopped a little to improve the contrast range for better computer screen viewing.
I have attained fairly normal (say a 4 stop range) level of contrast on more recent experiments, but the pictures themselves don't look as nice.
This was on some highly expired Ilfospeed Grade 3 RC, in 6x6 format. I find better results come using full strength developer, and a flash to reverse the negative.