I am expanding/converting a legacy Web Forms application into a totally new MVC application. The expansion is both in terms of technology as well as business use case. The legacy application is a well done Database Driven Design (DBDD). So for e.g. if you have different types of Employees like Operator, Supervisor, Store Keeper etc and you need to add a new type, you just go and add some rows in a couple of tables and voila, your UI automatically has everything to add/update the new type of Employee.
However the seperation of layers is not so good. 

The new project has two primary goals 

* Extensibility (for currently and future pipeline requirements)
* Performance

I intend to create the new project replacing the Database Driven Design (DBDD) with a Domain Driven Design (DDD) keeping the Extensibility requirement in mind. However moving from a Database Driven Design to Domain Driven Design seems to inversely impact the Performance requirement if I compare it to the performance of the legacy DBDD application. In the legacy application any call for data from the UI would directly interact with the Database and any data would be returned in form of a DataReader or (in some cases) a DataSet. 

Now with a strict DDD in place any call for data will be routed through the Business layer and the Data Access layer. This would mean each call would initialize a Business Object and a Data Access Object. A single UI page could need different types of data and this being a Web application each page could be requested by multiple users. Also a MVC Web application being stateless, each request would need initializing the business objects and data access objects each and every time.
So it seems for an MVC stateless application the DBDD is preferrable to DDD for performance. 

Or there a way in DDD to achieve both, Extensibility that DDD provides and performance that DBDD provides ?