Having attended enough Grand Rounds on this subject and occasionally guiding patients, I have reasonable familiarity with principles of sleep hygiene that I routinely violate or make excuse to justify non-compliance. My sleep times are generally not maintained since I often doze off early due to deprivation the night before. Getting up at the pre-determined time seems to go well, with little variation between work days and off days. Where I probably go astray is use of the bed for a variety of activities for which it was not intended, from reading to TV to iPod, as my comfortable sanctuary with a warm down comforter that serves me well in all seasons. We have opaque shades, always closed, so that the room has artificial light all the time. This tends to be a bigger problem with getting up than with staying asleep, but I overcome this by going downstairs at 5:30 most mornings where curtains are kept open allowing plentiful daylight.
For the most part, the purpose of sleep should be to enable activity the next day, so in that sense I am not particularly incapacitated by this, though I sometimes wish I felt a little more energetic by the time I get home most evenings. Will definitely have to be more firm with myself in adhering to the modifications that may leave me more rested most mornings.