Re: Adding a new file as if it had existed

"Bahadir Balban" [off-list ref] writes:

Is there a good way of adding new files to git as if they had existed
from the initial commit (or even better, since a particular commit)?
This way I would only track the new changes I made to an existing
file.

No.

I do not understand why not adding all the files you care about
eventually anyway in the initial commit is needed for
"performance reasons", if you do not touch majority of them for
a long time.  Care to explain?