1. the legends cape gives +7 to all defensives and was the number 1 cape in runescape for a long, long time. also it only costing 600?gp it is still quite the bang for the buck. obby cape used to be over 300k in comparison. 2. lousy piece of rag? uhh.. actually if you are 60 defense the d sq is great for mages and rangers. i remember when i hovered at 60 defense i loved my d sq. furthermore if you look up old Mage staking videos, nearly every mage used one as defense from melee. 3. because white knight armor only requires 10 defense. having identical stats to black armour (besides prayer bonus) it gives 10 defense pures a great chance to look great and get extra prayer. again, the white knight armor was released wayyy before prossy.