How to save black clothes black?
Answers: You're doing a lot right already. Woolite (and other cold-water detergents), specifically the dark-colors formula, single make clothes rough if it's not rinsing out completely. A second rinse cycle solves that problem, if it occur. (The rough-clothes crew is probably either over-packing the clothes, too lots for the load, or putting within too much Woolite, BTW.)
I second the inside-out and the cold water. The dryer doesn't give the impression of being to have any effect on intensity of blackness, within my experience.
Fiber content is the biggest factor by far. Anything with more than more or less 30% cotton is going to fade, because cotton simply can't hold onto dyes as well as synthetics.
FWIW, I know of goths and metal folks who routinely buy black dye and re-dye their faded black clothes. They don't resembling Rit, but another brand which is a cold-water dye. Sorry, I'm blanking on the name. IIRC, it starts beside "A".
There is a certain detergent specifically specially made for dark clothing. I can't remember what it is, but I use it and it seem to be working. Also, if the whole article is black then you can dye it again surrounded by the bathtub. Or you can buy those dry-cleaning plenty from the grocery store and instead of washing them you can dry-clean them contained by your dryer. That's what my hubby did with his more expensive jeans. They worked too.
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