I think it might be helpful to step back from it all and just consider how coarse/fine your adjustments are, at the three phases:
(1) exposure
(2) development
(3) print
At the exposure phase, you can theoretically rate your film however you choose and thus affect the CI in a continuous way.
However! Note that most cameras and meters do not allow rating and exposure compensation changes smaller than a third or a quarter stop or so. So in the end, you don't have that much flexibility in how you rate your film. Also, relatively small rating changes (say, 320 compared to 400) can make really big differences with some films (just try bracketing!). So on the whole, I'd say that adjustment in (1) exposure are quite coarse. To put it another way, exposure is not a truly continuous variable- you'll tend to settle into EIs that are discrete values, like 200 or 320 or whatever suits your fancy. Nobody says, oh yeah, I get the best results when I rate tri-x at 247.3
(Well, maybe Ron does that ...) These coarse EI adjustments are the logical starting point for most photographers.
At the development phase you have two truly continuous variables that you can tweak: dev time and agitation. Indeed there are other variables too, but time and agitation are the two that most people fuss over. Note that you will see folks saying that they develop for 6 mins, or 6 mins and 5 sec, or 6 mins and 10 sec... and if you press them, they will also have some prescription for how much agitation and exactly how that agitation is done etc. You can make many
very fine adjustments in the development phase. Therefore it is logical (to me) to start experimenting with development after you have made the coarse exposure adjustments.
Now, the last variable is the (3) contrast grade. And some would say (myself sometimes included) that this is a variable that you'd really love to freeze, so that you can just work with one paper grade etc... but good luck with that! :rolleyes: One reason why I don't like to fuss with contrast grade and split grade etc. is that you can find yourself doing a
lot of work to get really minor changes in highlight and shadow transitions. To me, it's much more fun to have the exercise of printing reduced to some minor dodging and burning.
N.b., the BTZS logic goes through this loop of variables in a somewhat similar fashion but in reverse order, so to speak. In BTZS, you think about the constraints of the print first, and then work backwards through dev and exposure to try to make your printing task as easy as possible. If you are more or less settled on film and developer and paper choices then this can be a very efficient way to go. I, for one, am not settle don any of those things, so I just ask myself roughly how I plan to print and accordingly I shoot and expose and develop for roughly more or less CI. But truth be told, it's quite rare that I have a specific print in my head when I am out taking photographs. Usually I am too concentrated on the experience of the scene and trying to walk away with as much information on my neg or chrome as possible. So, to me the printing phase is something I'd happily fret later, or even cede to someone else. At this point I am enjoying the act of going out with a camera much more than the act of printing or showing people my prints. Everybody looks at this differently, of course. To some, my approach above is total blasphemy, I am sure
Anyway, BTZS logic is every interesting and everybody should think about it at least once.
Maybe I should have added one more phase before all of the above, namely:
(0) Metering
...but people's metering practices vary widely, corresponding to the film they are shooting and their desired amounts of shadow and highlight detail etc.
i cant develop per negative (35mm) but i would like to get a better overal development. you say putting my shadows in zone 3 and try to adjust development for the highlights?? could it be usefull to do a zone test?? to use a psuedo zone system?? 
