Another thing to note that tanking wise Shinobi helps skills scale better. Gungho as seen from a DPS perspective falls off, however gungho adds 600 threat/hate points to your damage, that is significant. Same can be said for concentrate. Since in safezone for opening burst it really does not matter the trade offs of the skills in def etc. Also Thrust while lack uster can still provide utility thus added a large amount of value to s1 where for all other builds it becomes more valueless to a sharper degree as you level.
tldr; tanking adds value to swordsman skills
