Hi Eli,
Thank you for your response.
You actually pointed out a specific redirect that was in place, but what we were redirecting didn't exist i.e 301 redirect /tag/ThisExists-ButThisTypoDoesnt - do you think that would be the cause? Although, if the tag/post didn't exist how did Roger pick it up, through htaccess?
We are in the process of redirecting our /tag and /category posts to more appropriate pages. I will re-crawl and see if the same issue pops up fingers crossed.