About Skewing Witness Lines
You can skew the witness lines of only one dimension at a time. When you skew the witness lines of a dimension, the witness lines are inclined according to the movement of the skew dragger. You can skew witness lines in a direction parallel to the dimension’s leader line. You can skew witness lines of dimensions with Z-extension lines.
You cannot skew the witness lines in the following cases:
If dimensions have a single witness line.
If dimensions have witness lines that are on opposite sides of the dimension leader line.
The witness lines snap to their default positions when you move the pointer near the default location of the witness lines.
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You can skew only the witness lines of linear dimensions.