I don't know if the feature is available in version 2.2, but the
development version (2.3) is currently able to "lock" the control points
in a manner similar to what you describe by holding down the CTRL and
SHIFT keys while moving either of the controls in the Edit Mode.
> I would like at least one particular option that is
> available in both Inkscape and PS: to be able to 'lock'
> the control points of a single point such that the line
> joining the two control points intersects the point
> itself (i.e. the two control lines are parallel)
"It is amazing what you can accomplish if you do
not care who gets the credit." -- Harry S. Truman
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