If you take a good look at ANY complete armor set you will notice that it has all the bases covored as far as stat enhancements... Full suits of a particular type of armor is meant to ballance the stats across the board... Don't think this is usefull... think again. After mastering pottery, poison making, smithing, and tailoring with a pathetic 73 int, this little item would have been cherished.
Watch the generalizations. Do a search on 'Woven Shadow' (this set of armor), and you'll get 7 items returned. Look over the stats listed, and you'll notice that there are no enhancements to charisma or poison resist. (NOTE: No poison resist is odd for rogue armor.)
It's not true that ANY complete armor set will cover all the 'bases'.