Best workflow when re-scaling a clip?
 

Hypthetical situation: I have some 1280x720 raw footage, and my end product will be a 640x360 web clip. I want to take advantage of my "extra" pixels to fix some framing glitches, although for some of the footage I will be using the entire original image.

Which of the following would be the better workflow (and why?):

1) Create a 1280x720 project, scale the footage UP for the segments where I wish to adjust framing, then export as 640x360.

2) Create a 640x360 project, and scale the footage DOWN for those segments where I wish to retain the entire original image, then export as 640x360.

Thanks in advance.

IMO scaling down is always better than scaling up, so I would take approach 2.

Harm, that's been my inclination also. However .... someone just drew my attention to interesting this Cineform blog post: CineForm Insider: Oversampling

"We often see user setups that run the larger source media on a timeline that matches the target resolution, e.g. 4K source in a 1080i/p timeline. This seems to be an obvious configuration, but I'm going to point out why this is the wrong way to setup your project... "

My workflow has always been to output the edit in its native format.

Framing corrections are more easily done if you don't need to retain a 16:9 aspect.