My Public/Private Pages are not displayed in navigation option

Steps to reproduce the issue:
1. Add the following properties in portal-ext.properties then start the server:
user.groups.copy.layouts.to.user.personal.site=false
layout.user.private.layouts.enabled=true
layout.user.private.layouts.auto.create=false
layout.user.private.layouts.power.user.required=false
layout.user.public.layouts.enabled=true
layout.user.public.layouts.auto.create=false
admin.default.role.names=User
2. Create a user groups "TestUG" with private pages
3. Create a new user "A"
4. Assign to user "A" to the "TestUG"
5. Login as "A" and click the dockbar "Go to"
Unexpected result: My Private/Public Pages are not displayed in navigation option.

The behavior varies from 6.1 GA1, 6.1 GA2 and trunk.

<< In 6.1 GA1
Only if we grant the view permission to the group pages, these two options are displayed.

<< In 6.1 GA2
These two will NOT be displayed even if we grant the view permission.

<< In trunk
These two will be displayed no matter if user has view permission.

Moreover, if we set layout.user.private/public.auto.create=true, the behavior is also different.

<< In 6.1 GA1 and trunk
Default Welcome page is not created.

<< In 6.1GA2
Default Welcome page is created.

I guess we may need to have a standard concept about what is the expected result then diagnose if which one is the bug, which means:
1. Assume we don't want default Welcome page being created by setting layout.user.private/public.auto.create=false, but the user inherited pages from group and he has the view permission for the group page, should user be able to get the My Private/Public Pages displayed?
2. Assume we set layout.user.private/public.auto.create=true, and the user has inherited pages, should the default Welcome page be created.
3. It seems the permission check is implemented for the first page, so it does matter whether the default is created or not.