Uh... Im really tired of Partridge's theories... I know he would be a great Red John, I thought he was Red John till the beginning of season 6 and then I started looking at facts, reading interviews and putting things together.
OK Jack Plotnick (Partridge's actor) said that he was playing Partridge as he was Red John the whole time. That's why everyone is so convinced that its him.
Its a trick that Heller played to us so everyone will believe its him till season 6, and yes he has too many fans that still stick to him.
Additionally, the actor that plays Red John said he was stunned and fluttered when he learned that he will play Red John, which ofc doesn't fit with Plotnick who was playing Partridge like he was Red John.
I try to minimize the people that write Partridge theories because its getting annoying, Partridge is not Red John please choose someone else and stick with him otherwise you will be really disappointing.
Please read his interview here: http://www.tvequals.com/2013/09/23/exclusive-interview-the-mentalists-jack-plotnick-talks-playing-brett-partridge-being-a-red-john-suspect-flies/
I wanted to note that Red John didn't just killed Partridge but he also hit him, he had bruises on his faces which is a little bit weird. For me it indicates that he did something wrong and Red John punished him. Best thing i can guess is that he gave away himself as not being Red John and reducing Jane's list to 6 suspects when Patrick looked him in the eye.
Sorry if my post disappointed you,,, but please dont trick yourself, open your eyes, do not just see what you wanna see otherwise you will be blind to the truth.