If I could do a longer trip around a race, personally I would make the *trip* part come after the race...so race day(s) followed by park-only days, and not the other way around. The food for me would be an issue, but more than that I'd have trouble staying off my feet before the races.
In 2012 the decorations were still up during marathon weekend, but the marathon itself was on January 7: the first Saturday in January. This year they were not up (marathon was January 13, second Saturday in January). My guess is that they won't be up during the weekend itself in 2014 or 2015.