What if...

[Pocket-God]

King Kai had taught Piccolo Kaioken, how does the Namek Saga change?
Oh and assume Piccolo can use it more or less as well as Goku can.

 

[Let's Go Fearless!]

Then he can force Freeza to transform to his true form and might use 50% IMO.

 

[withheldforprivacy]

Probably, he gets cocky, prolongs Freeza's torture and allows him to go 50%.

 

[Let's Go Fearless!]

Also if Piccolo learn the Kaioken then he might not merge with Nail since he would be determine that he could take Freeza with ease.