Difficult to know where to start with this one. I'm sorry you've clearly had a bad experience as a councillor but just as there are bad clerks, and councillors, there are good ones too and when the two work together the benefit for the residents can be clear.
Having been on both "sides" I am a very firm believer in compulsory training for both clerks and councillors. I also acknowledge that the ridiculous legislation we have to work within is well past its sell by date. The councillors job is to make decisions for the benefit of the area they serve and the clerk's role is to facilitate that decision making, ensure decisions are within the power of the council to make and are carried out in accordance with legislation and recommended practice.
I have never understood the need to withhold access to background information. As a clerk, I would have been delighted that a councillor showed an interest in ensuring the council acted within the legislation!
I'm sorry I don't have an answer.