Inconvenienced when using Contact Content Provider on Android

These days, I've been developing an application that reads and writes entries from/into Android Contacts.
Everything goes fine until I need to insert email entry into Android Contact by Contact Content Provider API.

This is how to insert a people or phone entry into contact (people, phones table):
getContentProvider().insert(People.CONTENT_URI, values);
getContentProvider().insert(Phones.CONTENT_URI, values);

That's fine according to
http://code.google.com/android/devel/data/contentproviders.html

However when I insert an email entry into contact (in contact_methods table) using:
ContentURI uri = getContentProvider().insert(ContactMethods.CONTENT_URI, values);

It just returns null, nothing inserted, and nothing shows up on logcat.
Why? the link above says it should be fine!
To find the answer, I post a thread in Google Group:
http://groups.google.com/group/android-developers/browse_thread/thread/9ed4ff7fc1338b7c
However no response.
then I have been diving into build-in Contacts Application for 2 days to find how Google used their own api.
Luckily, I got the key.
see details on my another post:
http://zeaster.blogspot.com/2007/11/how-to-decompile-dex-file-on-android_28.html

You should insert an email like this:
ContentURI uri = People.CONTENT_URI.addId(user_id).addPath("contact_methods");
ContentValues values = ...
uri = getContentResolver().insert(uri, values);

why? I guess Google should provide one same way to insert content.

That's the main inconvenience.
I guess what's even worse is Google does not provide enough docs or log warnings for this tip.
Here are the others:

2.
when insert an email for a not-created-yet user id, It's still inserted successfully.
when the user id created in the future, the user would have the email address.
I guess Google should prevent this happen.
Actually many checks Google need to do.That's really a beta SDK.

3.
The content provider API is not Object-Oriented enough.
I feel it tedious to use.

4.
Maybe this is greedy.
I hope there is API to manipulate database that's similar to ActiveRecord for Rails.
Maybe I will implement one like that if time permits.