Piccolo and the Earthlings not learning Kaioken

[ahill1]

Why do you imagine they didn't learn it? Maybe they were just not capable of such, but considering how much Piccolo did power up from just 6 days, I imagine he should be up to the task.

 

[Future Warrior]

It would have been cool to see at least Tenshinhan using it.

 

[Pocket-Gog~]

I think it's quite simple, they were neither as skilled nor talented as Goku was. Even Kaio the creator of the technique couldn't use it, so I don't see why Yamcha and friends wouldn't be able to use it as well.

 

[SSJ2]

Piccolo learning the technique in 6 days would be absurd, regardless of the massive gains that he made in that span. Kaioken is not a technique one can just pick up with ease. Given the fact that Piccolo's BP increased so much during the 6 days, it's clear that was his focus - not learning the Kaioken technique.

The humans not learning it is questionable given they had over a year to learn it, but Gog's explanation probably works best. Plus it's arguable that Tenshinhan incorporated part of the technique into his Shin Kikoho.

 

[Boo Brand Milk]

It may be English anime filler but Piccolo tells Android 19 they can amplify their ki in short bursts at will. Apparently they already have a comparable technique. Once you get over 100k hi risk amplification is probably a given.