Auto Motion in Excel
I'm surprised you didn't suggest that Hanan Cohen implement auto motion with a macro. That avoids the trap you use as the reason you think auto motion is a bad idea -- if the user implements the macro then it's their responsibility to remember they're using a macro, and it's their option to turn it off again.
From what I can remember of this discussion thread, an auto motion macro (or rather, VBA) in Excel wouldn't be too difficult.
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