She's a perfect doctor!
Imagine an injured squad of ninjas during the war. And that squad gets attacked by squad of 3 chuunin and 1 jonin, for instance. Then they say: hey, doctor, we are bad and havenopride so we'll kill u AHAHA!
And Tsunade says: hmmm... not rly >.<
Squad: Wtf?
Tsunade: Mm well dunno
Squad: WTF, Our movements are fucked wtfff
Tsunade: oops, sorry "blow"
squad dead