New geometry "compoundCurve"

[dbeckerAC]

For a standard compound curve (i.e. (line)-spiral-arc-spiral-(line)), the following geometry tags are necessary:

<line length="400" />
<spiral length="200" Rs="0" Re="150" />
<arc length="150" R="150" />
<spiral length="200" Rs="150" Re="0" />
<line length="400" />

My idea would be to combine the spirals and arc into a new tag compoundCurve (the lines could remain the same) which could look like this:

<line length="400" />
<compundCurve Ls1="200" La="150" Ls2="200" R="150" />
<line length="400" />

The code should lead to the same result

Do I miss anything that prevents this idea?