My site only has ~700 pages in google. I currently do not have tag pages in my sitemap. If I added them, I would have ~5000 pages. I'm wondering if any of you have experimented with this. I would consider my tags pretty accurate, but not perfectly distributed.
True, you should noindex them there is no reason to have them indexed or to pass link juice to these pages. You can do this in robots.txt or using the noindex tag.
Tag is a optional thing for sitemap which i do not use in my sitemap and i haven't set up tag as do follow, because i do not want to share my link juice.