Big differences between Vanguard and Morningstar

So I decided to take a look at my asset allocation this morning to see what a few months' changes have done to it. I went to Vanguard and found these basic numbers:

• Value/Blend/Growth looks like 25.6/45.4/8.0 (with 21.0% in international)
• Small/Mid/Large looks like 14.6/18.8/45.5 (again, 21.0% international)

To doublecheck, I went to morningstar's instant x-ray and entered all my funds and amounts. The result was this:

• Value/Blend/Growth looks like 28.8/26.5/23.3 (with 21.4% in international)
• Small/Mid/Large looks like 7.8/22.6/48.2 (again, 21.4% international)

Now, in my understanding, the concepts of value and growth and small/mid large are pretty concrete-- they depend on fundamental characteristics of each stock. So why such dramatic differences between M* and Vanguard?

My inclination is to think that Vanguard classifies a fund as value/blend/growth and small/mid/large, and then assigns every dollar in that fund into that classification. So a small cap value fund will go into the portfolio analyzer as 100% SCV, even though it may contain some portion of mid cap stocks or growth stocks. M* probably breaks it down to the stock level. That would explain why they differ.

But this is still disturbing to me, primarily because I arranged my entire portoflio to tilt toward small and value. According to M*, I failed at both. There is barely a value tilt (28.8/23.3) and my tilt toward small is instead a tilt toward mid. This aggravates me because I am specifically invested in funds that lean that way, and SURELY they do not stray so far from their title as M* sugests. I could not possibly have lost nearly HALF of my small cap stocks as M* suggests. Surely my small cap funds aren't just half small cap. And surely a small cap value fund isn't 40% value, 40% blend, and 20% growth, which is what M* is suggesting.

I'm thinking that my belief in how Vanguard analyzes your portfolio is correct, and thus it's not totally accurate. But I think there has to be something wrong with M*'s instant x-ray as well. There's no way that my growth content, which Vanguard reports as 8%, could really be 23.3%. I don't see how that is possible with my portfolio containing several index funds that specifically emphasize value and not one fund emphasizing growth.

Has anyone else noticed this? If you have a vanguard account with your outside account info typed in (which is nice, btw), look at their portfolio analysis tool and compare it to M*'s instant x-ray. Tell me if yours looks as wonky as mine.