I think theory is only going to expand your creativity. While most people can easily hear major scales, pentatonics, and blues scales, and create w/them without any theoretical knowledge, how many people are born with the natural intuition to hear whole tone or diminished scales and be able to apply them in a musical manor.
I know....Allen Holdsworth, Django, and Charlie Parker! But there a small part of the population...the rest of us mere mortals are forced to find alternative ways of reaching such profeciency.(and hopefully before we reach 65 and arthritis sets in)