Mapping paths with different number of dimensions/branches

When connecting streams from different areas of my definitions I find myself using the PathMapper a lot to ensure that there is a one to one mapping between the paths in each stream. Should I be doing this, or is grasshopper able to map two paths that have a different number of branches?

For example consider I have two data streams as follows.

Curves
{0;0;0} Curve A
{0;0;1} Curve B
{0;0;2} Curve C
{0;1;0} Curve D
{0;1;1} Curve E
{0;1;2} Curve F
{0;2;0} Curve G
{0;2;1} Curve H
{0;2;2} Curve I

Distance
{0;0} Distance X
{0;1} Distance Y
{0;2} Distance Z


Now say I want to extrude each curve by the respective distance. What I would typically do is use the PathMapper to partially flatted the curves stream like so:

{A;B;C} -> {A;B}

However, I think it would make more sense if grasshopper could just map paths with a different number of indexes.

For example the path {0;0}  would map to any other path that begins with {0;0}. So in this example would be the following.

{0;0;0} Curve A
{0;0;1} Curve B
{0;0;2} Curve C

Does grasshopper already do something like this? If not does anyone else think it would be useful? How else have people been dealing with merging complex tree structures.