Believe it or not, he's probably right. I know of very experienced traders, guys who have been at it 20 or 30 yrs, that lament the lack of reliable, clean data. Most of these guys check their data against 2 or more sources and manually correct it themselves everyday. H
It is practically impossible to correct the CSI data yourself because after you corrected it, CSI will change it back after the next data download and distribution.
send inquiries to CSI. i did yesterday. if they get one hundred mails within a week, they will change it. actually my experience with them is very good. i think they are very good, yet not perfect. at least they save me a lot of time.