I guess I never had a problem popping the light off my bike to plug it into the work computer. I don't see how that's any better or worse than popping it off the bike to change a battery, be it rechargeable or not.
My headlight has an 18650 in it but it hasn't needed replacement yet.
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Genesis 49:16-17
"Well, well!" said Holmes, impatiently. "A good cyclist does not need a high road. The moor is intersected with paths and the moon is at the full."