There is 100% segmented run available on this site - watch the run, do all the things that are done in the run - and you will get 100%
Gonna bump this since I don't plan on watching a 7-9 hour run since I could just ask with more detail.
Would a 100% include all of the assassinations, races, tombs, etc., and if so, do they include the Templar Lairs/Auditore Crypt from uPlay?
Would it also include the 8 statuettes, all the feathers, all the weapons and other upgrades, a 100%'d Monteriggioni, and would you have to open up every single chest in the game?
100% is just full synchronization. That means all main missions and all side missions (beat-ups, races, assassinations, courier missions, tombs and lairs), and it does include all the Templar Lairs/Auditore Crypt from UPlay. This doesn't include statuettes, feathers, weapons, upgrades, 100% Monterrgioni, and opening every chest.
I'd like to suggest that the rules for the various runs be updated. For example the 100% run should detail the response to the question above. I also noticed that the w/Warps category for Any% says Warpless in the rules, which is an easy fix. I'd also like to ask what constitutes a warp. Is there some glitch/exploit I don't know about, or is a warp referring to fast travel? Maybe that could be cleared up in the rules too.
A warp is teleporting to a spot on the map. Reloading a checkpoint during a mission, changing outfits, and save+quitting/quitting+reloading constitutes as warps. The in-game fast travel system is considered warping. Warping abuses the game's spawning system. The game doesn't save your exact spot on the map, it saves what "zone" you are in, so when you reenter, you spawn at the designated point for that zone.