I mentioned 3 points... Unfortunately all negative points:

1.  The crisis is nothing to do with Identity.  It is regarding DB design. I believe all agree on that. 

2. This is about the various ways you can identify identity values.  Unless we have a performance issue or do are planning to modify the system entries, using system functions is the best way to retrieve the identity value. This point leads to the third argument.

3. I am sure Performance is not an issue in identifying the identity column, and current value. Is the author planning to change the values? Yes.  If he is going to manipulate system tables, those information are useful.  Otherwise what’s the point of accessing system tables? That is my final argument.  How these system table values helped him to change the data type. Unless he specifies that, that part is not useful.

I am sorry, The article isn't useful to me.