No matter what your style, you can and should sing in tune. If you have pitch problems your listener will be, to some degree, distracted by the dissonance. This doesn't mean you have to hit every note purely with no slides up or down or bends. Much like a truly brilliant steel guitar player (Robby Turner, Sonny Garish come to mind)... your sliding has to have a "center" of pitch that feels like you know where home is!
Sass makes some great points about style, and I love that she ends with the fact that your should never think about competing with another singer when developing your style. However, neither should you accept your inadequacies as "style". With vocal training, you can do things you never could otherwise.
In this present atmosphere of tuners and digital editing, you can no longer get by with out of tune singing. Sing with excellence.. every time and every place. Then you'll need no excuses. And by the way... lordy, Sass Jordan can SING!