[tablatures] Could I get a critique on my first lilypond tab?

[Patrick Horgan <phorgan1@xxxxxxxxx>]

Anything anyone wants to tell me about better slicker more elegant ways
of doing the same things would be awesome. 

I'm attaching the lilypond file for Let Him Roll, a Guy Clark talking
blues.  He essential plays the same thing over and over.  What I've got
covers the main two variations.

I couldn't find anything that covered hammering and pulling with H and P
either under or over the tab or on the slur line, so just followed the
suggestion to use an appoggiatura for a hammer for something that
switched notes on the beat, and a grace notey sort of thing for a quick
hammer that just borrowed a bit from the beginning of the note for the
original note before the hammer.

I'm not sure how you would know the difference between a hammer and a pull.

You'll see my attempt to put H at appropriate places doesn't work. 
Apparently a TabStaff is missing whatever engraver would put them in?  I
can put them in the regular staff, and it works, tucking them under the
Chords, but it's not at all what I want.  Help!!!;)

Patrick

\version "2.13.45"

\header {
  title = "Let Him Roll"
  subtitle = "by Guy Clark"
  subsubtitle = "tablature by Patrick Horgan"
  copyright = "Copyright Guy Clark"
}

\layout {
  indent = 0.0
}

hammersNpulls = \relative c {
  \time 4/4
  \key c \major
  \voiceThree
  \stemUp
  s1 s1 s8^"H" s8 s4 s8^"H" s8 s4 s8^"H" s8 s4 s8^"H" s8 s4
  s1 s1^"H" s1 s1
  s1 s1 s1 s1
  s1 s1^"H" s1 s1
}

thechords = \relative c {
  \time 4/4
  \key c \major
  \voiceThree
  \stemUp
  s1^"C" s2 s2^"Cadd9" s1^"Fmaj13" s1
  s1^"Em7/G" s1^"G7" s2^"Cadd9" s2^"C" s1
  s1^"C" s2 s2^"Cadd9" s1^"Fmaj13" s1
  s1^"Em7/G" s1 s2^"Cadd9" s2^"C" s1
}

upper = \relative c {
  \time 4/4
  \key c \major
  \voiceOne
  \stemUp
  < c' g' >2. <g c g'>4     | <c g'>4. g8 e' d c g(   |
  a) d ~ d g,( a) d ~ d g,( | a) d ~ d g,( a) d ~ d4  |

  d4. r8 d e ~ e4 | \appoggiatura e8 <d f>4. <d g,>8 ~ <d g,>8 g,4. |
  d'2 r8 c ~ c g  | r8 b ~ b4 e f                                   |

  % repeat with variations
  < c g' >2. <g c g'>4 | <c g'>4. g8 e' d ~ d4   |
  d2 r4 <a d>          | a8 d ~ d g,( a) d ~ d4  |

  d4. r8 d e ~ e4 | \appoggiatura e8 <d f>4. <d g,>8 ~ <d g,>8 g,4. |
  d'2 r8 c ~ c g  | r8 b ~ b4 e f                                   |

  \bar ":|"
}

lower = \relative c {
  \time 4/4
  \key c \major
  \voiceTwo
  \stemDown
  c4 e g, r   | c e c e     | f f f f | f f f f    | \break
  g, d' g, d' | g, d' g, d' | c e c e | g, d' g, b | \break
% repeat with variations
  c4 e g, r   | c e c e     | f a c,2 | f4 f f f   | \break
  g, d' g, d' | g, d' g, d' | c e c e | g, d' g, b |
}


\score {
  <<
    \new StaffGroup = "tab with traditional" <<
      \new Staff = "guitar traditional" <<
	\clef "treble_8"
	\context Voice = "theChords" \thechords % Put chord names in
	\context Voice = "upper" \upper
	\context Voice = "lower" \lower
      >> % regular staff
      \new TabStaff = "guitar tab" <<
	\context TabVoice = "hammersNpulls" { \tabFullNotation \hammersNpulls }
	\context TabVoice = "upper" { \tabFullNotation \upper }
	\context TabVoice = "lower" { \tabFullNotation \lower }
      >> % guitar tab
    >> % staff group
  >> % score
}