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music on the 5 string,for me it is definitely easier to use a plectrum,as I have acquired that skill with the four string,hence my >>>. ..question regarding four finger style,having acquired that skill on the guitar, it is thus easier...is there a logical musical reason for not doing this,other than it has not been done before...>>>

The four finger style that guitarists use has been tried lots of times on 5 string banjo. What you will get is a banjo being played in the style of a guitar, not a style that is characteristically banjo-istic.

As noted above, there are a zillion styles of banjo playing. Pete Seeger's book will make this clear. While it is true that you can do anything you want, I urge you to learn one of the traditional styles - 3-finger, frailing or similar. This is the only way to understand the particular approach to syncopation that has been preserved by 5-string players ever since the early Africans brought the banjo to these shores.

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