Powershell and SP 2010 question - trying to understand get-spsite

When I read http://technet.microsoft.com/en-us/library/ff607998(v=office.14).aspx I see the statement:

"You can view the current user interface status by generating a list of all Web sites in a site collection and their corresponding visual upgrade data. " The code example that is provided is:

$sc = Get-SPSite http://machinename/sites/collectionname; $sc.GetVisualReport() | Format-Table

So. the first thing I try is

> get-spsite http://myfarm/*

and I get a list of all the site collections on my farm.

So, I then try

$sc - get-spsite http://myfarm/* ; $sc.GetVisualReport()

and I get an error saying that GetVisualReport isn't a known method.

So then I remove the * and run things and I get a list of results that appear to be the visual report for sites associated with myfarm.

Question 1: Why didn't the * work for GetVisualReport when it returned what appeared to me to be a series of objects?

Next, I started looking at the output. Some of my sites have a USVersion of 3 and some 4. That's cool.

Then I wanted to verify the information. So I randomly picked one of the WebPath values, addedhttp://myfarm to the beginning, and pasted it into my IE URL input box.

I get an error that says that the page cannot be found.

Question 2. How did it get returned by get-spsite if it cannot be found?