User blog comment:Kaido King of the Beasts/Chapter 870: There and Back Again/@comment-3529684-20170630005707/@comment-130.102.82.79-20170704051640

Planning to shoot big mom has nothing to do with it. Sanji just can't personally attack a woman. He has no problems with his allies doing the attacking as evidenced by the various female foes the straw hats have encountered.

Sanji is simply defending against big mom. He definitely won't be the one involved in fighting all out against big mom. The whole thing about only using his shin to defend against Kalifa is ridiculous. How are you even comparing the threat posed by Kalifa to Big mom? Sanji was much stronger than Kalifa. He simply held back to a point where he knew Kalifa wouldn't be hurt. Same thing here, diable jambe sure as hell isn't gonna hurt big mom. Another key difference is Sanji is willing to go easy on a woman at the expense of himself, but it's a different story when he's protecting an even more important woman.