Focus Gain Glitch

I think I may have found a version of the problem.  The focus meter covers 100 units of focus per bar.  On my monster screen, each bar is 3.5" long and I'm sure that on smaller screens it is smaller.  That means that each unit of focus represents .0035ths of an inch.  Going up by only a few units of focus doesn't register visually.  I have found that even when the focus meter doesn't appear to move, if I go to the character menu, I see that I've gained some small amount of focus, in the 2-5 unit range.  So what people are calling a "Focus Gain Glitch" may be a "Focus UI Glitch" instead.  There is gain, you just can't see it.

One experiment I thought was strange was that I was testing whether focus was divided among the group and sent my Inquisitor out alone near the swamp camp in the Frostback Basin.  Killing a tusket netted me 5 focus (280 to 285), but then killing a gurgut and even using a combo in the process, netted me only 2 focus from 285 to 287.  And this was while wearing the Master Belt of Focus (+35% gain).  Killing another tusket straight up, no combos, got me 4 focus, to 291.  Killing another gurgut with a combo, got me 4 focus to 291.

All I can surmise is that there is some sort of randomization to the gain.  Also, if focus gains are always this low, the belts are pointless, because a percentage gain over a low amount doesn't increase it significantly.