Q:

Guitar tab plugin (jTab) should be active only in questions tagged [guitar]

I see that the jTab guitar tab plugin has been introduced at music.se now as it was on guitars.se, which I think is brilliant.  But it should perhaps be only applied for questions tagged [guitar].  I just posted an answer to a Harmonica question, where I needed applied note names in a monospace font, and was converted to guitar tabs when I added.  I had to simulate the spacing to get it work without code section. 
Example of jTab kicking in, although I don't want it to be:
C    D    E    F    G    A    B    C  
out  in   out  in   out  in   in   out 

Instead I had to do some hacking using the block quote format, and add some &nbsp; to align the spacing to an approximate:

C   -  D -  E -  F -  G -  A -  B -  C
    out in  out in  out  in  in  out 

On StackOverflow, the programming language to use for code coloring is based on the language specified in the question tag ([C++], [C#] etc.  use C encoding. [ VB6], [VB.NET] etc.  use VB encoding and so forth).   

A:

A temporary workaround I've found is to use HTML <pre></pre> (preformatted text) tags around stuff that would otherwise be malinterpreted by jTab. 
EDIT:
Lilypond makes great use of << and >> symbols.  These will get screwed up by <pre> tags unless you encode them as &lt;&lt; and &gt;&gt; respectively.  Groan. 

A:

If anyone else is still struggling with this 5 years later (as I have been), I used inline ticks. 
My problem: I wanted chords to appear thus, with the notes spelled out:
C Dm Em etc... 
C D E ...
E F G ...
G A B ... 
However when using pre-formatting (four spaces before text) I obtained the jTab chords, so instead I used inline ticks with line breaks
`chord name here`
`Chord notes`

which stopped the automatic jTab rendering.