to suggest that carpet cleaning knowledge isn't important is a little bit misleading,
I know a lot of carpet cleaners and ALL the successful ones have 2 things in common the have an extensive knowledge of all aspect of carpet cleaning and they charge high prices.
you can have all the marketing knowledge in the world and the phone can be ringing off the hook but in the end you need to clean a carpet and do it well. I've seen lots of marketing campaigns sky rocket through the roof but they never keep going unless the end product is good,
marketing is what boxers do before a fight , but its all waffle until they step into the ring and do the business.