git add without whitespace

I think it would be useful to have a '-w' option for 'git add' that completely ignores whitespace changes, the same way that 'git diff -w' does.

Real life scenario:

Sometimes developers will use tooling that does not properly strip trailing whitespace in source files. Next time I edit those files for a simple 1-line code change, my tooling will strip whitespace from the whole file. I *do* want these changes, however I want 2 commits: 1 commit with the bugfix, and a supplementary commit with just the whitespace changes.

At the moment, there is no way for me to conveniently add the source file to the index without whitespace. The only way to accomplish this today that I'm aware of is via this command:

$ git diff -U0 -w --no-color | git apply --cached --ignore-whitespace --unidiff-zero

This command explicitly leaves out context because it can sometimes cause the patch to fail to apply, I think due to whitespace being in it, but I'm not completely sure myself.

It would be useful to be able to do this instead:

$ git add -w

This would effectively function the same as my workaround command shown earlier. It should also be valid to use -w with -i and -p. In the -p case, it just won't show hunks containing whitespace changes. For -i, it would assume '-w' as part of any command run during the interactive session.

Does this idea sound good? I have some free time on my hands so I wouldn't mind implementing this. Maybe there isn't a huge audience for this kind of thing, or maybe I'm just going about this the wrong way. Thoughts would be much appreciated.