Not all food empties or moves through the system at the same rate. In other words, the meat, fat, vegetables, and starch travel at differing rates. Other influences on motility, is the size of the meal/bolus, and how distended the stomach becomes. Increased distention, stimulates motility. The texture or consistency of the food is important. Solid, ground, pureed, and liquid foods, move at differing rates. People who chew their foods longer, have greater motility and absorption changing emptying time.

I think you're okay to wait 2-3 hours, but 4-5 is safe. So, if you have dinner at 6 and go to bed at 10pm, take your med at bedtime and you'll be good to go. At my hospital (I'm a RN), all levothyroxine (Synthroid) is given at 10pm. My understanding is that the protocol changed because several peer-reviewed studies found better results, perhaps do to the reasons you suggested.

Make it a bedtime ritual.