Comment 3 for bug 290439

Further to my above comment, directly from http://www.mythtv.org/wiki/index.php/Frame_display_timing

"If MythTV will be using the RTC to time the display, it will usually request a high interrupt frequency, allowing it to time frames more precisely. However, unless MythFrontend is a privileged process, the highest frequency that it can request by default is 64 Hz. This is usually not sufficient for CRT monitors that are often set to a higher frequency, usually 85 or 100 Hz, as well as some LCD screens and projectors that can accept various frequencies, producing the tearing artifacts as mentioned earlier. The most common solution is simply to increase the maximum frequency that an unprivileged process can request from the RTC."

This indicates the tweak would be used to improve video output performance, more of a frontend function.