Playing while making the decisions you'd normally do isn't without its downsides. For instance the path that came naturally to me was the good one. It was only thanks to Kthulian's option to change your alignment that I discovered that the route changed so early and that I would be with Bredita once I woke up if I chose to be evil. Bredita is my favorite girl and the femdom route also seems to be part of the evil route while evil options were the most counter-intuitive to me so I can definitely see the value of a walkthrough.
Not to mention that a walkthrough could also let you know about little things you might have otherwise missed, like some extra dialogue/CGs with Liliana because you went to the Archmage at once instead of checking random rooms first. It could also show the location of some extra goodies like gold or books that might be easy to miss and could be helpful for the people that don't wish to cheat. So far it doesn't seem necessary but I've always appreciated walkthroughs because at the very least they can put you at ease that you haven't missed anything you'd want to see or do.
Not to mention that a walkthrough could also let you know about little things you might have otherwise missed, like some extra dialogue/CGs with Liliana because you went to the Archmage at once instead of checking random rooms first. It could also show the location of some extra goodies like gold or books that might be easy to miss and could be helpful for the people that don't wish to cheat. So far it doesn't seem necessary but I've always appreciated walkthroughs because at the very least they can put you at ease that you haven't missed anything you'd want to see or do.