The problem you need to solve: Time Tracking Fields (Estimates Time, Spent Time and Worklog) need more security than JIRA provides.
How Minyaa solves this problem: Minyaa try to offer different solution to enhance the security.
Minyaa extends Issue Viewer in order to apply the Screen Rendering for the Time Tracking Field.
In other terms, if you remove the Time Tracking Field from the Edit Screen definition (Screen associated to the Edit Operation), it will not be displayed in Edit Screen and also in View Screen.
As soon as the Time Tracking Field is removed from View and Edit Screen, it is possible to allow som authorized users to edit it, following the below steps :