@djsundog @outie @mcc it's also cos the semiconductor they use (GaN) is just so ridiculously efficient at producing blue light that as soon as you bias the LED past its minimum current by a tiny amount it goes off like Gandalf's fuckin' staff.
also doesn't help that your eyes adjust to scotopic vision in the dark, which has a really high luminous efficiency for that wavelength of blue. it's pretty much the worst possible form of light for any product that might go in a bedroom.