It is also possible to hit the string with both a down and an up movement of the index finger, and I am curious to how far you can take this effect--is it possible to to a tremolo while the thumb role is going?

Mark Clark--Rick has dropped part of the secret, and that is the simple and discreet mention of Mose Rager, which is usually done as Rick has done it, by beginning with Ike Everly.