Well, I'm thinking it could be ok, but I personally wouldn't bother. I would either let it sit for 3 weeks and then rack into the bottling bucket, or get another carboy (a 5 gallon one) and rack it. You really want to keep the beer from getting oxygenated, and racking it twice just to clean the yeast out of the bottom is exposing it unnecessarily. You'd rack it a third time to the bottling bucket to bottle it, and I think that's just not the best idea. Probably won't hurt it, but more risk than benefit in my opinion.