Why must I use UserControl.MousePointer instead of Me.MousePointer? - vb6

Question

In VB6 on a UserControl, I must use UserControl.MousePointer = vbDefault instead of Me.MousePointer = vbDefault. I can use Me.MousePointer on a Form (and Form.MousePointer doesn't work).
Why must I use UserControl.MousePointer instead of Me.MousePointer?
I mean literally the text "UserControl", not UserControl as the placeholder for another control name.

Answer 1

Me isn't what you seem to think it is. It is a reference to the current instance of the module you use it in, not "magic."
To get what you want you must add this property to the default interface of your UserControl, e.g.:
Option Explicit
Public Property Get MousePointer() As MousePointerConstants
MousePointer = UserControl.MousePointer
End Property
Public Sub Test()
MsgBox Me.MousePointer
End Sub
In VB6 Forms are a little different, probably as a holdover from 16-bit VB to make porting old code easier. These always seem to inherit from a hidden interface. This is defined in a type library you don't have access to since Microsoft did not release it as part of VB6. Attempting to query it typically comes up with an error like:
Cannot jump to 'MousePointer' because it is in the library 'Unknown10' which is not currently referenced
From this alone it seems likely that using Me always carries a small performance penalty. Instead of going directly to the module's procedures it appears to me that you are going through its default COM interface.
You'd have to inspect the compiled code to determine whether there is a performance penalty, and if so how much. I don't see this documented so otherwise we are just guessing about it.
In any case there is little reason to ever use Me unless you must in order to qualify something.
Crummy example but:
Option Explicit
Private mCharm As Long
Public Property Get Charm() As Long
Charm = mCharm
End Property
Public Property Let Charm(ByVal RHS As Long)
mCharm = RHS
'Maybe we do more here such as update the user interface or some
'other things.
End Property
Public Sub GetLucky(ByVal Charm As Long)
'Do some stuff.
Charm = Charm + Int(Rnd() * 50000)
'etc.
Me.Charm = Charm 'Here we use Me so we can assign to the property Charm.
End Sub
That's really about the only legitimate use for Me anyway: scoping to the desired namespace. Relying on it because in typing it brings up IntelliSense is just lazy.
If anything Forms are "broken" not UserControls.

Answer 2

Figured it out. It turns out that since a UserControl is an ActiveX control, VB6 does some magic for you. With a Form control, it's not an ActiveX control which is why the MousePointer property is accessible via Me, like you'd expect.
For UserControl's, the UserControl control you create in VB6 sits on another control - the ActiveX control. That ActiveX control is accessible via UserControl. Something like this:
class ActiveXControl
{
int MousePointer;
VBUserControl control;
}
class VBUserControl
{
}
class YourUserControl : VBUserControl
{
ActiveXControl UserControl;
// we must use UserControl.MousePointer
}
but for a Form, it's more like this:
class Form
{
int MousePointer;
}
class YourForm : Form
{
// we actually inherit from Form so we use Me.MousePointer
}