Problem I see here is why are there splices at all ?.
All wiring should terminate directly on the
dimmer lug. If there are multiple outlets being energized from a single
dimmer, the splicing should be elsewhere, preferably on a
terminal block in an exterior cabintet.
All wiring going to lugs should be neat and
bundled, only long enough to reach the lug and there's really no need or desire for "extra"
wire in the rack. One good reason is it interferes with air flow
thru the rack.
I had the same issue with the electricians wiring my
dimmer racks back in '04. I took them down to another Sensor that had been wired by one of our campus
IBEW electricians, which was letter perfect and told them this was how it was to be done, it's in the spec's. The fixed all.