that's a lot of fiddling. if i want to develop films of different speeds and/or types together, i'll just use a two-bath developer. from asa 25 to 400, it all works well because development time is not a variable. Anchell/Troop TD-200 or divided D-76 is what i use. you can't push or pull the film, and you get some highlight compensation using this method, but you get proper film speed (aka shadow development). i've done Adox CHM 400 and Ilford Pan F+ in the same tank.