Please see this example from illustrator:
When drawing with the pent tool; holding CMD allows the point to stay smooth while changing the length of the next off-curve point. This would be extremely useful.
Edit: I realise I have posted about this before but the last time the answer was to use “Clean up paths”, that does not always work since the angle I end up with is not always smooth enough if I use the existing method of holding Alt and turning it into a corner.