Gate length in time division

[XORadmin]

And so the use of the table keeps each step length the same and so the pattern remains synchronized, as opposed to just setting SCLK fx's in the track itself.  Correct?  If I wanted to control gate length with higher fidelity than 6ths, I can increase groove default settings and run at higher bpm?

Yes a step length is not changed with a table. It can be changed with the groove setting.
1/6th is indeed the shortest gatelength for a regular 6 groove. And I am not sure about the use, but this would only be nicely audible with low BPM.
If a higher resolution is needed (indeed for lower bpm) then you could always change the groove per step to like 12 which would allow a 1/12 resolution for each step. But it would also half the real bpm for that.