Re: Mel Bay's Picker's Guide to Bluegrass Improvisation?
Here are two prior threads about it:
I know there's one or two more recent threads that are really good ... as people have had more time to get into the book, more people exposed to it.
I found it a good value, as it walks you through moveable pentatonic playing and then works toward full scales, blue notes, and double stop riffs.
I found it very useful for the above development, it gave me lots of little pieces that I can attach to more straight melodic playing to make a more ornamented solo which follows the chord progression. There's a massive amount of exercises and stuff to work through - the accompanying CD is of mp3 files, hours and hours [instead of 72 minutes total per CD].
I got this book a while ago, for where I was it was a great help and one of the better instructional books I got. I've only gotten more time/use out of tunebooks, this and the JazzMando book have lasted - I'm still doing stuff out of them both 1 year+ into having both books.