If I understand correctly:
You can remove the pizz. node by dropping an ‘arco’ or ‘nat.’ technique on your score.
‘arco’ seems to just remove the pizzicato node, and leave everything else alone.
‘nat.’ seems too drop all nodes and take you back to your ‘Natural’ technique.
Some techniques do NOT have a ‘fallback’ assigned to them. If that’s the case, then you’ll need to figure out what’s missing and add it to your expression map.
For example: Lets say you’ve added a con sordino technique to a string stave. A few bars later, you might add pizzicato. If you discover that it’s still playing arco then you’ll need to add more techniques in your expression map, or simply send a nat. technique first (clears all the nodes), and then send the pizzicato.
By having lots of seemingly duplicate entries, we make it more possible to toss just about any technique we want anyplace in the score and instantly swap ‘stacked’ effects. It also makes it less essential to clear out our nodes (nat.) before building up a new articulation set. In this case, we could also be sure to get a ‘muted’ version of pizzicato.
Example:
Natural
legato
Accent
Staccato
Staccatissimo
Pizzicato
No Vibrato+Natural
No Vibrato+legato
No Vibrato+Accent
No Vibrato+Staccato
No Vibrato+Staccatissimo
No Vibrato+Pizzicato
Vibrato+Natural
Vibrato+legato
Vibrato+Accent
Vibrato+Staccato
Vibrato+Staccatissimo
Vibrato+Pizzicato
Muted
Muted+legato
Muted+Accent
Muted+Staccato
Muted+Staccatissimo
Muted+Pizzicato
No Vibrato+Muted
No Vibrato+Muted+legato
No Vibrato+Muted+Accent
No Vibrato+Muted+Staccato
No Vibrato+Muted+Staccatissimo
No Vibrato+Muted+Pizzicato
Vibrato+Muted
Vibrato+Muted+legato
Vibrato+Muted+Accent
Vibrato+Muted+Staccato
Vibrato+Muted+Staccatissimo
Vibrato+Muted+Pizzicato