Damir Dobrić post interesting article ("Is ADO.NET reliable") on his blog about unexpected results using ADO.NET.
His sample made me think of: we all use a lot of built-in classes from many sources (core, WPF, WWF, WCF, factories, guidance packs, app blocks etc.), market push us to adopt more and more, quicker and quicker and the truth is: we should be very careful combining those bright new shiny things and putting them into our systems. For example, the book says: “Windows Workflow Foundation managing the multithreading for you so you can think of the business side of your application“. Great tip :( - not. And of course if we combine WWF with my DAL from Ent. App block and some other new technology and put it /of course/ in a web application… we should know what we are doing ;-) …
As Sledge Hammer says: "Trust me, I know what I'm doing!"