[css-transforms-1] Focus definition of neutral element to the needs o…

…f SMIL. #932

css-transforms-1/Overview.bs

@@ -576,11 +576,9 @@ With this specification the SVG basic data type <<transform-list>> is equivalent
 Neutral element for addition {#neutral-element}
 ----------------------------
 
-Some animations require a neutral element for addition. For transform functions this is a scalar or a list of scalars of 0. Examples of neutral elements for transform functions are ''translate(0)'', ''translateX(0)'', ''translateY(0)'', ''scale(0)'', ''scaleX(0)'', ''scaleY(0)'', ''rotate(0)'', ''skew(0, 0)'', ''skewX(0)'', ''skewY(0)'' and ''matrix(0, 0, 0, 0, 0, 0)''.
+Some animations require a neutral element for addition. For transform functions this is a scalar or a list of scalars of 0. Examples of neutral elements for transform functions are ''translate(0)'', ''scale(0)'', ''rotate(0)'', ''skewX(0)'', ''skewY(0)''.
 
-Note: Animations to or from the neutral element of additions <<matrix()>> fall back to discrete animations (See [[#matrix-interpolation]]).
-
-Issue(w3c/csswg-drafts#932): Replace text and simply refer to `null` value?
+Note: This paragraph focuses on the requirements of [[SMIL]] and the extension defined by [[SVG11]]. This specification does not provide definitions of neutral elements for the other transform functions than the functions listed above.
 
 <div class="example">