Hi @architect.civil5.
I just tested the fix for RH-58905
The developers have already added a Through Pt option to the Polyline commmand Arc option in the Rhino 7 wip 2020-6-5 or later in record time.
Command: _Polyline
Start of polyline ( PersistentClose=No )
Next point of polyline. Press Enter when done ( PersistentClose=No Close Mode=Arc Helpers=No Direction ThroughPoint Center Undo ): ThroughPoint
You can see the fix in action here in a video here.
Those that have a Rhino 6 license can download the latest Rhino 7 WIP from here
Let us know if this works for you.
Sincerely,
Mary Ann Fugier
McNeel Technical Support and Training
Seattle, WA