The bleach spot is a nice gray shade. Here, take a closer look.
I couldn't bear to throw them away when I was packing. I thought, what if I bleach the whole pair of pants? Will they all be the gray color?
I didn't have anything to lose. Obviously, I am not going to wear the pants with the spot so I might as well experiment. And, today I finally conducted the experiment.
There were no methods, no steps, no hypotheses - I just filled the sink with water, added bleach, and tossed the pants in (actually I place them in gently so that I would not get more splatter spots on my clothes). In a few minutes, the water was black.
Wow, that's a really bad picture of my pants soaking in bleach water.
So, I emptied out the black water and started over again. Then, I totally forgot about my pants until an hour later! I laid them outside to dry and this is what they look like:
It isn't a completely even color, but I think they will work for hiking, wearing around the house, and walking Ransom (if it ever gets cool enough). Here's a side-by-side before and after:
Definitely more wearable sans obvious-spot-in-awkward-place.
Since I don't really have much success on home-projects, I am pretty happy that this actually worked.