Well stated Geoff.
I dealt with this much earlier in this posting thread several years ago but will reiterate here:
Thomas Woodward, originally from Connecticut, had relocated to Hopkinsville, KY prior to the war. He formed the Oak Grove Rangers, in a town that borders TN and KY, that was mustered in as a Tennessee cavalry unit initially (for some reason - some of its members were from the Clarksville area) but became part of Helm's 1st Kentucky Cavalry, a one year regiment, in June/July, 1861. The Rangers had become a three company battalion by this time.
After Helm's regiment disbanded in June, 1862, Woodward returned to the Hopkinsville area to recruit what would become known as Woodward's KY Battalion. It was in this formation that he, along with Adam Rankin John (who was then forming the 10th Kentucky Partisan Rangers), captured Clarksville, TN in August, 1862. Woodward's battalion went into west Tennessee to join Forrest for a time, fighting at Parker's Crossroads in late December, 1862.
In early 1863, this battalion fell apart, and Woodward recruited his own 2nd Kentucky Cavalry which remained for the rest of the war, as Geoff has stated, albeit without Woodward who was canned as unit CO for several reasons (including probably not writing ANY reports that would have appeared in the later Official Records). He was killed attacking Hopkinsville in 1864 while trying to raise yet another command (although I doubt the War Department would have let him keep it).
Greg Biggs PS - if you think these KY cavalry units were confusing try dealing with North Carolina units!!!!