"In fact, on a piano you get an instant bluesy effect by playing F natural and F# simultaneously against a D chord. Have a go."

I see [I mean hear] what you mean, greg. Thanks.
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"using your key of E examples you'd get: E,G,G#,A,Bb,B,D,E"
This too sounds good, although I personally would find it hard to do. Going up the scale, this has 7 half-steps in in. Chromaticity indeed! My choir leader told us that half-steps add emotion to music. This scale is certainly packed with it.
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"If you are playing in the key of E and start on the second note of the E scale (F#) and bend up to the third note (G#)..."

What's meant by "bend" here? I'm familiar with bending note on the flute. What do you do on a guitar?
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Thanks for the history, Jay.