Here is a quick demo of the power of knowing the chords to a piece of music ... knowing them inside and out, all over the fretboard... seeing the whole fretboard as 'the chord'. This is the progression I used in one of my fingerstyle lessons, in fact I've used the very same mp3 as a backing track. If you'd like to try this out, you can download the mp3 from that page.
As you probably know by now, when I improvise melody over a piece of music, I don't think scales. I would have very little success creating a solo over anything thinking scales. That's not to say that others can't ... but I wouldn't know where to begin thinking along those lines, especially in a piece like this that introduces a bunch of 'outside chords' into the picture --- chords not in the key of G. Once that happens, you would need to start thinking of different scales and modes for different sections and then somehow merging them into melody. Way too hard for my poor old brain. The fact is though, the chords of the piece have already, by their very nature, selected the strongest melody notes: their tones ... the notes that make them up... Chord Tones.
It doesn't matter how many 'outside' chords come into play if you're tracking the music one chord at a time, and you can see its tones scattered the length of the fretboard instead of boxed in scale patterns. One way or the other, you need to think of something, and since you need to know the chords anyway, why clutter your brain with a whole other set of patterns? Not only that ... if you were to come up with a nice melodic solo thinking scales, you would find if you analyzed the lines that they would in fact be mostly chord tones. Why? Because Melody Loves Chord Tones. That's simply the nature of music, that's how it works. If it's melody you're seeking, look to the chords, not the scales.
This demo is certainly not meant to be an award winning melodic extravaganza! I purposely played only chord tones so you can hear that they work, they're right, they don't clash with anything, they fit ... I did this so you can see that it is possible to, first of all, see them there for each chord, and that once you can see them there, that they can strung into melody that isn't just plucking notes from a chord. In other words, playing just chord tones needn't be boring. Most of the chords used in this have 4 or more chord tones to work with.
I used my index finger to make it a little clearer for you, and also to show that muscle-memorized runs and riffs aren't coming into this. I'm hunting the chord tones down ... seeing them and stringing them together as I go, thinking a little ahead so I know which chord is coming up, hearing the evolving melody in my head, steering it to a pleasant resolve ... listening, steering, listening.
You can take my word for it that all notes played are chord tones ... or you can pick it all apart and see for yourself. If the chord is a plain old major, I use the 1-3-5 of that chord; if it's 7th, the 1-3-5-b7; 9th? 1-3-5-b7-9; minor? 1-b3-5; minor 6? 1-b3-5-6 ... etc. The melodies are simply the result of stringing those chord tones together ... timing, dynamics, taste also come into it, of course, but the choice of notes is dictated by the 'chord of the moment' ... not the 'blues scale'.
Seeing them there is the trick, and I won't tell you how I do that. My book/DVD PlaneTalk explains and demonstrates that trick ... it's very simple, but takes a lot of work putting it into practice. Once you digest it, though, you can see the entire fretboard as a chord, and no chord is trickier than any other .... they're all the same, all friendly, all familiar.
If I were playing a proper solo to this, I wouldn't restrict myself to just chord tones ... you'd hear a few--and I do mean a few--non chord tones in amongst it all, adding detail to the picture. They are a piece of cake to see and use once you can see the chord tones ... they are, of course, other scale notes and chromatic scale notes (thinking 'modes' become redundant ... I'm playing all kinds of modes in this without once thinking about them) ... in other words ALL 12 notes become easy to use once you can see and use the CTs. They can link two CTs together, or add tension if lingered upon, generally embellish and add color to the CT melody that lies at the core of it all.
The progression is:
| G - - - | - - - - |G7 - - - | - - - - | C - - - | - - - - | Cm - - - | Cm6 - - - |
| G - - - | E7 - - - | A7 - - - | D7 - - - | G - - - | Edim - Am7-5 - | G - - - |
I hope this helps you understand the power of knowing your chords! If you know your chords well enough, you know all scales and modes also.