mted; have a listen to the pete seeger playing the banjo thread, recorded in 1949.he talks about old scotch ballads that arrived in america 200 years ago,and links them up to american banjo playing.
now I grant you there is also a blues,as well as a country and old thyme influence in bluegrass ,the blues scale and the bluegrass scale are the samething [Albeit against different chord sequences,and used slightly differently].
however most of the singing has a much stronger old thyme appalachian influence,here is a quote from the back of a stanley brothers vinyl lp..
THE STANLEY BROTHERS are one of the few acts that consistently experience good sales of country tunes and MOUNTAIN BALLADS.[its these mountainballads that came from scotland etc].now please dont tell me ths Stanley brothers are not bluegrass, WHAT IS CLINCH MOUNTAIN BACKSTEP[ To my mind they are closer than merle travis[dark as the dungeon and nine pound hammer have been included in folk collections and the latter in traditonal finger picking FOLK styles,In my opinion Merle Travis was a folk country crossover,his songs may be covered by bluegrass artists but they are also covered by folk artists.
check out Jean Ritchie, Doc Watson, Clarence Ashley ,and then woody guthrie AND MRS TEXAS GLADDEN singing in pete seegers film AN OLD BALLAD
what Pete Seeger effectively says is that in the south the two traditons met. end product to my ears BLUEGRASS ,..
jimmie Rodgers who was not BLUEGRASS was more interesting incorporating the swiss yodel, twelve bar blues,on occasions jazz players like Louis Armstrong, EarlHines.
I hope you are not going to try and say that there is no connection between bluegrass banjo and other American banjos styles.