I have found that the time to pull the print from the first dev and put into the second dev then flash is approx 1/2 the total dev time, I use 2 min twenty seconds.The print I find would be just emerging blacks at this halfway point.
The more exposure on the print will produce more real *no effect* the more dodging you do will also allow you to get more effect and the mackie line. I like playing with these balances to produce a real and unreal print.
The dodging tool is very effective weapon as well as heavy burn.
I like very strong negatives ie contrast, for lith printing and solarization as well.
If you do a lot of lith printing it will help in solarization as your skills at pulling a print in the developer is very helpful in solarization as the fun is when and when not to put the paper in the stop bath.
The effects are endless, I have found that all papers work with this process some better than others. I use the two Ilford fibre papers as in solarization if I want real silver looking prints I will use MG4.
Contrary to the idea of using grade 4 papers for solarization I have found that grade two works well for my needs and tastes.
The possibilities are endless but I would be using a metol based developer only for the most control.
the William Jolly articles are absolutely the best descriptive articles I have found on this subject.