Code editor lags when editing a test method name

With the test runner enabled, when I edit a test method name the VS code editor responds very slowly and characters typed appear after a long delay. It appears that for each character that is typed the test runner is performing some heavy operation (probably to determine if the method is a valid test method). Also, uncommenting a block of code containing 20 test methods can cause VS to get stuck or stutter for upwards of 15 seconds.

It is easy to demonstrate that the TypeMock test runner is at fault (and not .some other add-in like ReSharper) by performing the following:

1. Try to edit a test method name. VS lags considerably.
2. Add the [DontRun] attribute to the test method and try to edit the method name. VS runs as smooth as butter.

It turns out that with a Core i7-2600 and 16 GB of RAM it's quicker to add [DontRun] before editing the name and remove it after than waiting for the lag (especially if you have to correct typos). But doing that can become really old, really fast.