That's hardly worth a post. But I did re-look at the photographs so here are a few excerpts that show variability of surface treatment.
The exterior of an H32/58 of the late 3rd/early 4th AD. Shows thick unbrushed slip on surface. The photo is a little washed out, overall color of the vessel is "normal" ARS orange.
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The interior of a similarly dated H53a. Thick, somewhat smoothed surface with feather rouletting.
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It would be really nice if I had a good photo of a very smooth H50. I'll look for one.
Interior of an early 6th century H87b. Less detail than the previous two. Thick smoothed slip.
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Exterior of the same piece. Obviously thinner slip is "streakily" applied.
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