Can anyone plz tell me, why this snippet pair only works once? (using getTVValue and setTVValue methods)

Still fighting with this problem ...
Filed a bug at MODx bug tracker:

http://tracker.modx.com/issues/8360

I also tried to run this snippet as a plugin at the OnLoadWebDocument event - but same result!
TV is only updated once and after clearing cache. And the problem still only persists in Articles resources!

User @Uncle68 posted a workaround:

https://forums.modx.com/thread/73758/my-page-counter-stopped-working-in-2-2---tv-cache-issue?page=2#dis-post-411528

Can confirm this works!