Where do you put your code?
I have a friend who is constantly saying he can write code much faster by configuring the various data controls with the SQL insert, select, update, and delete statements. I tried this. It is true the page was much faster built. A few clicks, a few typed attributes. However, and this is a big however, that style of coding makes several assumptions. Under each assumptions, I'll also list why I think a middle layer needs to exist between the GUI and the database. For those of you who are laughing that I even need to make this argument, beware what project you take over. Look at the code first.
you configured the controls correctly the first time
In order for the process to truely be fast, you can only touch it once. With a code library, you can easily grow the middle layer to suit all your needs without having to retouch that page using a data control.
you don't have any need to use that code again in that web app, ever
Whatever you write is what the user, admin, etc see - one interface only. I know this is bogus but it's the only thing that backs up a "much faster" arguement. With a code library, you can have as many views into the data as you need. But, yes, you do have to write that code.
you don't test your code beyond it's first unit test
In order to test this type of code, it's either by hand or a high-end gui/web tester. With a code library, there are several tools to unit test including nUnit or it's new version xUnit. Once you have the unit test, you can run your tests against every build. The unit tests will find error before your customers do - which is so much nicer.
no one else will ever touch your code
Few decent programmers would work this way. It says you are lazy and work alone.
those controls will never change or be removed
In order to get the full benefit of time savings, it has to live for the life of the project. However, with the middle layer, the logic can live beyond that app to any other app or variant. Of course, you could totally munge the library into a piece of #$% but both approaches assume the design skills are solid.