That's incorrect. Just second ago failed str check with my 45 str and 3 persuasion warrior against 28 str Murga.
it is not incorrect and this anecdote does not prove your point
persuasion works dynamically in this game but a common theme is that it values persuasion levels over stat levels
sometimes, a character with a higher str stat will fail a str check but succeed a wits or memory check. this is because each option has its own chance to succeed independent of your stats or persuasion level
a better way to go about using persuasion is to look at who you're talking to and figure out if the persuasion option, dialogue-wise, looks feasible. str options tend to involve intimidation, but if you are trying to intimidate an ogre or a confident warrior, you are likely to fail
this is because the game writes persuasion into the game rather than making it a flat stat check you can pass or fail; some checks will be literally impossible, while others will be passable with zero levels in persuasion