whooo, you're getting into some complex (or rather tedious) work there... we've done that a handful of times in traditional/manual code, in dnn FormMaster, and in XMOD and XMOD PRO. it's never as simple as you might imagine. most of the time it involves building up a hidden value list that is passed from form tab/page one all the way through to the end to get to final submission, and any number of quirks or user issues can cause issues before you get to the end.
what's the purpose of having 8 tabs of related form content? are you saving to the db at each step, that way a user could abandon the process between, say, tab 4 and 5 and you'd still have all of their submitted information?
that's about the best legit urgency for breaking up forms that we found... when we were doing insurance estimate forms, it was clear that for lead generation, they wanted to get the info from a user even if they only filled out page 2 of 5, etc.
Otherwise, if you're not saving in between steps, and you're just breaking up the visual presentation of the form questions among 8 tabs... they maybe consider having it all in one form, all one tall page, and then tasking JQuery with taking groups of questions broken up in DIVs and then visually presenting them as tabs. Or other types of JQuery-based content scrollers or paginators, there are plenty of approaches for showing content in bite sizes |