I'm not that a fan of Devin Harris. I'll take Rondo, I prefer point guards that can create for others .... and I think Harris' numbers are inflated due to the team he's playing on.
This is a really important point, actually. Not to mention that the only reason arguments like this are coming up is because Harris torched Nash for 47. I mean, I could score 20 against Nash. Harris is really good, but not THAT good.
That said, you're right -- it's awfully easy for decent players to put up big numbers on bad teams. Marbury's done it his whole life. Michael Redd, Eddy Curry, Randolph...there are tons of guys who are always on losers and are the team's no. 1 so they put up numbers.
I don't think this is the case with Harris -- I think he's a really good player -- but his numbers are certainly taking a spike because he's surrounded by very little offensively. (And also because he's not operating within Avery Johnson's 18 passes in 20 seconds offense.)