How can we better accommodate late changes to design?

The paper was originally presented at the WBF, this version is a bit more commercial.
www.controldraw.co.uk/presentations/Automationmethodology.pdf
The implementation of successful Control Systems depends on having accurate detailed information about the process under control. If the detailed process design could be completed before the control system is started then there would not be a problem.
However, it is in the nature of fast track projects that changes occur, information arrives late and detail continues to develop late in the detailed engineering phase.
For example:
Development of P&ID’s still continuing into the detailed design.
Valves and instruments get added during Hazops
Changes of scope removing and adding equipment
Details of process packages become available late in the detailed design
The users who are going to have to run the plant do not get involved until late, and then they wish to make changes and improvements to what they find.
On fast track projects the sheer speed of development forces the Control Systems programming activity into a short time period. That is only possible if the information is present.
Consequently in order to provide the systems on time the development process must support:
The ability to cope with frequent change.
A data store that can be added to as soon as the information becomes available
The means to identify information and its validity - for example its release status.
Key points of the methodology that results in fast progress are:
The Functional Design is detailed, reviewed and approved before code is fully implemented.
The design, review and implementation activities are carried out almost concurrently. This is of course phased so that the activities are serial for each small part of the project, such as one Unit.