Interesting answer. Given your response, I count two problems (not what I would consider "so many problems"), and also I take exception to me being "willing to inflict [danger]" on people. I'm assuming you meant that in a way that was less malignant, so I'll not take offense.

I should have mentioned my tires are rated for 60,000 miles, and are almost halfway there (I go through one set a year). Thus my concern about the likelihood of inclement weather. Likely I'll change them before I leave anyway, as I'm familiar with how my car handles in the snow. As for the mileage for those two days, I've decided to break up the SD/Montana stretch and the Montana/Seattle stretch (thanks to Couchsurfing.org), thus the longest day would be Philly to Chicago (If you cringe at 750 miles, then I can't imagine what you'd say about some of the days I did last year on my 15,000 mile roadtrip...) I'm in no rush to get to Chicago, but I simply despise Western PA and Ohio and wanted to cruise--going the speed limit of course--straight through, as I've no reason nor desire to stop and see anything.

What would the upward limit of a day's driving be, in your opinion? Keep in mind I'm not driving an RV or anything, but an Acura RSX.