So to avoid anymore unhelpful and sarcastic comments I shall add to my initial question.
I have been flying (and training) on the 800 for a few years now and have been taught to rotate the fan on every walk around by a few trainers for some of the reasons stated above. I was however told not to put my hands anywhere near the fan in recent times by a very experienced LTC, TRE and senior examiner. This confused me somewhat and caused me to seek clarification and learn something perhaps which might benefit my understanding.
I do check for ice on the fan blades in icing conditions but I don't turn the fan to do so.
I hope now you can understand the relavence of my questions.