BC didn't regulate my cycles...it just messed me up. I know several people who it has actually worsened their cycles... but I also know several people who it has worked for and regulated (like my sisters) so... I think it's more of a person to person kind of thing.
BC pills does regulate your cycle. I know so many women including myself that used it and helped regulate my cycles.
Hormonal birth control pills do regulate your cycles. Not sure what the LJ group is, but it definitely does regulate them in the average woman. I'm sure there are always special cases, but for the vast, vast majority of women, it works. If you are talking about something other than the pill, then it may be different.