May be a multipart (beginner) question. Context: not taking lessons. Reading a bunch of books but nothing really focuses on improvising/playing by ear.
When I try to play along with stuff on TV or radio, I would essentially try to sing the solfeggio and keep transposing it until the melody of the music fits in a 'major scale'. I'd then take the open C major shape and transpose the whole first 4 finger positions (open + 3 fingers) down the fretboard until it matches the transposed solfeggio I was singing. This essentially means (I think) that I can play along with any key in any major scale or natural minor scale with one single hand position. Though I'd like to get some feedback on.
1- I guess when I sing along, I can only recognize relative intervals by transposing the solfeggio. I have no idea if the note I'm singing is a A# or a G. If that note is the first H of WWHWWWH in the melody, then it's a 'fa'. Is this bad? How useful is it to recognize the note in absolute term by ear without trying to match it on a guitar?
2- When playing single notes along a scale, is it better to keep the 4 fingers along the same frets and use all 6 strings (and have access to 2 octaves-ish) or use fewer strings and change fret positions a lot?
3- By sticking to just one hand position, I suppose it means I only know 1 of the 5 CAGED shapes (is that what it means?). Is that bad practice?