When we made the playtest document for Tribes in the Dark available, we hewed relatively close to the FitD SRD in terms of the amount of content, which wound up being a 60-ish page PDF. There were some deviations, largely in terms of rules changes and setting-specific stuff (the playtest is doubling as a "quick start"). We got positive feedback on how we recomposed the FitD material, using a single column plus sidebar layout like Tribe 8 had.