Hey jkenton,
I've been thinking a lot about your situation for the last few days. Partially because my situation's the same, but in reverse. Wed-Fri are always busy, and Monday, Tuesday are quiet. So, I was trying to discern if that which works for me might be helpful for you. Here's some thoughts I've had about what might work. Perhaps you could try them, and then tell us if they don't work, and what about them wasn't helpful.

1) Thursday mornings is a good time to plan and implement a new practice. You'll have the free time to get anything together that you need, and to test it over two days to see if it's something worth carrying over into the next week. It's much harder when you don't have two days in a row where you can start the new habit.

2) If it's not working on your light days, it won't work at all. So, if you try a new habit and it doesn't fit well on Thursday, Friday, write it off as a learning experience instead of trying to fit it into your life. It's taken me years and I'm still tweaking my system to one that actually fits me, instead of me trying to fit into other people's systems.

3) If it does work, though, how about putting a large note on your computer monitor, or phone, or whatever it is that you check first thing in the morning. I'm even willing to go against the cannonical GTD and say to write it on your calendar if that's what you check first.

I can't remember whether it was here or the DIYplanner forum where it was suggested that any new habit you are trying to make should be on your ToDo/NA list for at least 30 days. I think that's key. We don't get into a new habit in a week. It takes at least three, and often more, if the habit we're trying to break is an ingrained one.

I'm interested in what happens if you try this. I'm only on week 3 of some new changes, so I can't promise that this'll work forever. For me though, wiring the change into my ToDo lists, my calendar, and physically putting a reminder where I can see it first thing in the morning have all been really helpful for me.