I kind of stumbled upon this as I was levelling my Leatherworking, as always check your server prices. The cost of Savage Leather is hovering at 4g50s per leather. Heavy Savage Leather is around 32g per item. Heavy Savage Armor Kit on the otherhand sell for 160 - 200g each.
Savage Leather x 5 @4g50s = 22.5g per Heavy Savage Leather
4 x Heavy Savage Leather = ca. 90g per Heavy Savage Armor Kit
Heavy Savage Armor Kit = 160 - 200g
These are supposedly pre Greater Mastery on a par with Mastery for tanks so a few will sell that way and maybe some people just have a stamina fetish that needs feeeding like in WotLK........ I am not a PVP'er so I am not sure how they stack up for BG's and arena's.
Check out your servers prices and market, maybe something in there for you.
Check out my earlier post Quick gold from Frostweave Cloth if you missed it.