I suppose it depends how effective you want to be at your instrument. It does make you a better player for sure but its probably a lot more helpful to use your ears if it sounds right and guitar is in tune then trust your ears unless your tone deaf of course. I tend to think harmonically using my knowledge of music theory to guide me around the fretboard and knowing in a certain key that particular shapes and fingering patterns will work on a certain chord. If anything learn as many different chords and their inversions as you can that will help you a lot more than memorising every single note on the fretboard, because of course if you use different tuning other than standard that will all be thrown out the window. If you dont already know learn some basic music theory jazz and classical, even the basics will cast a light for you and give you inspiration. Hope this helps.
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