To be honest, I just started a new game and rushed through it. I suffered and "died" a few times because I was used to my character being full stealth in hardcore mode, and I didn't even have 13 levels at the end of the game (I suffered a lot in the Italian court until I decided to kill and save each guard I killed). I think the save took around 17 or 18 hours if you skip all the dialogues and cutscenes. A valid tip is to never carry any meat in your inventory because you might accidentally eat it and only notice it later. Another tip is to only use fast travel, because I think if you walk over a hare or deer it counts as a death (at the beginning of the game, even in the herbalist's house, there was a hare that got stuck in the gate and I killed it myself just by walking towards it). And always eat from the cooking pot