Hi Gazelle,
We found it very difficult to stop the matting in our little Persian. Worst areas were around the tail and down the back of the legs. Particularly difficult in this hot climate of ours. She was totally indoor cat as well but the matting did happen very fast no matter how much we groomed her.

We had this comb that had a rattle in the end of it which helped her relax and play gently as we brushed her. Also helped to give her something to chew on as she lay there. We found it very difficult and the mats do start so close to the skin. I used to wonder if we spent too much time on brushing the soft unmatted area of the coat and should have been paying more attention to those other areas.

A couple of times we did take her to the grooming place and they seemed able to get the matts off just fine, but we also found that the colour of the new growth was different from the rest of her... not that it really mattered. Just an observation. I think it's easier and safer to do it with clippers if the mats can't be teased out with a comb. Scissors are too risky I feel.

I hope to hear advice from other people about how to help the problem.