Thanks Hugo. I read the blog and the Connect item.

Seems to me that things have changed since the Connect item, given the results of your tests.

If the information in the blog is still accurate, the only extra cost of SELECT * is metadata expansion at compile time: plan and execution time is identical. Good to know.

Conor's active blog is here:

http://blogs.msdn.com/conor_cunningham_msft/

I see your COALESCE connect item has been updated...