Mistakes when setting remaining estimates cannot be corrected for the burn down chart, possibly rendering it unreadable and useless.

A user may enter the wrong value for remaining time estimate, causing an invalid value of total remaining estimate time in the burn down chart. Though the value itself can be corrected afterwards, the burn down chart history can't be corrected. Especially when a user enters a value in weeks instead of hours, a relatively large spike shows up in the chart, which renders the chart unreadable and useless for the rest of the sprint, because of 'zoomed-out' scaling.

This issue also addresses this behaviour: https://jira.atlassian.com/browse/GHS-8477
(Marked as resolved by giving an excuse)

An (outdated) workaround can be found here: https://confluence.atlassian.com/display/AGILEKB/How+to+remove+mistyped+Estimate

I don't consider manually editing the database a viable workaround. (for OnDemand users, it isn't even possible at all). Because this issue causes significant loss of functionality, and the response/excuse from Atlassion so far triggered quite some negative reactions from users, I request this to be treated as a bug which needs to be fixed.

Suggested fix: Allow administrators to somehow undo or delete changes made by users.

(Since this issue occurs in Jira Agile, I file the it under the Jira Agile project. If the root cause lies in Jira itself, please let me know how to redirect it)