You can probably answer that yourself. That baxter trip is a couple of days at the least. Can you do 2 to 3 days in the whitesin a row Can you do a summit of washington, adams, etc, and feel like it wasn't the hardest thing you ever did? Is there any energy left - and feel totally wiped the next day. Can you recover? Only you can answer this.
I am kind of the same way. I doubt myself and then when the trip is done I always say - it wasn't that bad and I preferomed really good. I think the trick is that your in good enough shape to move a decent pace, minimal rests, and you are able to recover 100% after a short rest.
I am actually planning a trip to rainer hopefully for this summer/fall and been thinking about this topic alot.
I think I am ready to go west for some bigger climbs, Just to put it in perspective, I run at least 4 (try for 5) times a week with one run 7 to 10 miles, 2 runs at 6 miles and 2 runs at miles. ok - sometimes 5 times per week.
I can hike 10-12 per day miles in the northern pressies and then do it again the next day, the 3rd day is typically less miles.
I have not done katadin but will probably do it in winter 2005-2006. I don't have the time this year.
the biggest hurdle for me for rainer, hood, etc.. is the damn expenses to get out there and hire a guide, and plead with my wife to let me go.
As far was washington as a test for rainer - not sure. I think its apples to organges. I haven't done Rainer so if someone can help here, I think rainer would be more like doing washington 2 or 3 times in 2 days. I think it is like 20 miles R/T.
For rainer, it is wise to have glaicer skills if going unguided.