No. Even if you require no rest whatsoever you can still only work 8 hrs/day (or 4 hrs/day while adventuring).
Or just for balance reasons?
Bingo.
Your brain gets tired. Or something.
/Dissociated mechanics? What are those?
More rules lawyer threads. Not my favorite. Still...
If you shoot down any activity allowed by the extra awake time provided by the Ring of Sustenance, what exactly is the point of the less sleep ability?
No, you can't craft, cause the rules say x/day!
No, you can't move more or you're exhausted!
No, you can't read that book, because people's eyes get tired after that much reading!
I would allow any extra activity you want if you had one of these. It's magic.
If you're going to rules lawyer this ring into nonfunctionality, you might as well go further and follow the logic out. People who don't eat get tired, so I would say even with this ring, if you don't eat like everyone else, you'll be starving and exhausted the next day. You'll be irritable and quick to anger. You won't die from it, but you'll probably ruin your pancreas.
Wake up, people! The Ring of Sustenance is actually a CURSED ITEM!!!
Bleh
More rules lawyer threads. Not my favorite. Still...
If you shoot down any activity allowed by the extra awake time provided by the Ring of Sustenance, what exactly is the point of the less sleep ability?
The point is you get more useful time out of the day, and can prepare spells with only 2 hours of rest (though you can't recover slots that were expended in the past 8 hours). So instead of 16 usable hours, you have 22.
How you divide that time up is up to you, but the limits on crafting etc. are per day, and those limits don't change just because you need less sleep.
You can only craft a maximum of 8 hours/day (magic or mundane), and you can only create one magic item/day. But even with those limitations the adventuring wizard can get a lot of use out of this. If the party is stopping for more than 10 hours, then they can get 8 hours of work in (netting 4 hours of progress).
Wake up, people! The Ring of Sustenance is actually a CURSED ITEM!!!
Well, one side effect is that you have 6 hours when almost everyone else is asleep and you aren't. So that's 6 hours to just sit there and worry about stuff.
There's a good reason the no-sleep ability only contributes 500 gp to the price. It doesn't do much. Something that let you get extra crafting in a normal day would be really valuable for that alone.
It help when posting guard shifts for staying awake while resting in a dongeun or wildrenrss.
Its also a great for rp stuff:
Getting drunk.
Getting high.
Pulling pranks on sleeping party members.(messing with the wizards spell book. Getting the horse companion up some staris, as horses can go up stairs but not down. Etc..).
Fullfilling your rule as the:
Towns caped avanger. Towns crazy axe murderer. Bars late night special performer..