To me, even after riding clipless for over 2,000 miles I think I would probably crash if I tried to unclip with both feet to stop, can't imagine how that would work.

Think positive, and practice. For me practicing on grass didn't help because there was increased resistance from the grass with those skinnier tires and I felt more unstable on the uneven ground. I went to my favorite park with an isolated back road that looped and has no traffic outside of cyclists sprinting/etc. Sure, I crashed a lot during the 3 days of my failed first experiment...but 8 months later when I tried it again (after my muscle memory was quite comfortable with riding) the move was anticlimactic. I've only fallen twice in the over 2k miles since then - and one of those two falls was when I had a "Hey Vern, Watch THIS" moment"

So take your time, there is no law that says you have to start clipping in "x" period of time after starting to ride. Heck, there isn't anything that says that you EVER have to start clipping in. Some say that "to be a cyclist you must clip in" (I know a few who say this), but that is just silliness. There are people who ride a gazillion miles without attaching themselves to their bike. I only do it because my knee doesn't like it if I do not. I've had 75 mile road rides without clipping in. I do not clip in on the mountain bike.