Is it needed? Or can I just slick through it? I have no idea how to apply scales to chord progressions, I'm also an awful lead player (working on that), so my picking isn't exactly the best. I usually create some random semi-good sounding riffs, then mess around afterwards looking for the right chords. My apologies if this is a common question.
there are two schools of thought...some say yes...the study of music..can only be beneficial in a pursuit of working in the musical world .. some say it hinders creativity..though I fail to understand how knowledge is a determent to anything..

if you enjoy where you are musically at present..continue ..if it does not work for you..explore what may improve your playing,,take lessons..that may help a lot..and it does not require any theory..its like copy and paste..teachers shows you something..you play it..no why or how required...

now..If you want to know what your playing and why it works..I suggest you study theory AND harmony...a whole musical universe will open up for you..
play well

Just to be clear, there is no such thing as "guitar theory". Music theory is universal, it works the same way for every instrument.
Actually called Mark!

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I guess you could get by without it is you were strictly solo and played a style that was all your own, but any kind of ensemble playing, from duos to concert orchestras, is going to need some theory. For example, you would have to understand the concept of "key" and its implications for harmony. and melody.
It can't make you worse, but it depends what your goals are. If your primary skill is guitar and you want to do something with it (like make money), you need at least enough "theory" to communicate with other musicians, pick things up by ear, and play both lead and rhythm. If you want to be a singer/songwriter type, you don't need as much knowledge or technical ability.
Quote by steven seagull
Just to be clear, there is no such thing as "guitar theory". Music theory is universal, it works the same way for every instrument.
Oh yes, I realized my mistake when I posted the question, but didn't bother to fix it. But, hey I didn't know the theory was used for every instrument. Thanks for clearing it up though.
Music theory is the systematic description of music, and all instruments work together to make music, so music theory has no relation to any specific instrument btw

Also, "It can't make you worse" should be qualified - as long as you don't treat a description as a rule, you won't get boxed in. Making rules out of descriptions is a good way to get stuck doing a limited set of things over and over again.

There are things that people should know if doing Western music - intervallic relationships - that can be more clearly described with music theory ("that's a perfect fifth" vs. "the distance between frets 0 and 7 on one string"), and these intervals help define melody and harmony.
Learning how to describe rhythms also can't hurt, especially in a band context (hey, drummer/bassist, I want you to play X at such-and-such a time!).

Technique comes with time and proper practice; have you considered trying to practice songs you like to refinement? What is/are the reason(s) you think that you're an "awful lead player"? Maybe that will give you insight on things to practice.
"ba doo doo ba doo doo ba doo daa"
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