Extra effect when Scald is used by a Water-type?

… having 100% accuracy and a 70% 30% chance to burn, along with decent neutral coverage, makes it Keldeo’s most spammable move by far.

What does the 70% 30% chance mean? Is it just a misprint, or is it an effect of Scald when used by a Water-type? Because on one RMT here on the DataBase, I heard someone saying that Vaporeon made great use of Scald because of a “higher than average Burn rate”, or something like that. Is there a 70% greater chance of inflicting a Burn? I’m terribly confused!

Pleaselog inorregisterto add a comment.

Let see what each website say about Scald.

Has a 30% chance of inflicting burn on the target Pokémon. Fire-type> Pokémon cannot be burned.

Marriland.

Scald inflicts damage and has a chance 30% of causing a burn.

Bulbapedia.

The user shoots boiling hot water at its target. It may also leave thetarget with a burn.Effect rate: 30%

Serebii.» Scald deals damage and has a 30% chance of burning the target.

Pokemon DB.

Vaporeon makes a great use of scald because it is bulky. I assume they were referring to the rate a which scald burns which is 30% which is impressively high. That 70% part doesn’t make sense so ignore it