I've now been taking the valve apart each time, and did so again yesterday after using only 0.50 oz of hop plugs. This is what came out from inside the valve after soaking, and spraying thru with a garden hose, including cocking the valve half-open to TRY get out the gunk.
The valve does get quite warm from being so close to the boil kettle but the insides are not getting sanitized from the heat, in my opinion. I'd definitely recommend taking ball valves completely apart to sanitize. It does not have to be done right after the brew, just before the next one.