I vividly remember my first desalination megaproject of 110 MLD (US$ 120 million) which had a construction time of over 4.5 years (2003). We enjoyed learning and innovating and did not think about time value.
Today experienced EPC contractors may execute such projects in about 2.5 years. The economic benefits of shorter construction time are obvious: less cost of money and higher production revenues due to earlier operation commencement.

So what makes such a huge difference in construction times? The answer is concurrent engineering (CE).

There are many definitions of CE answering specific industries. For capital mega-projects executed in water treatment and desalination CE may be defined as follows.

CE is a holistic approach to project execution optimization under constrained resources resulting in shorter delivery times, better quality, and lower prices.

From the CE perspective, the macro-view of the project as a sequence of Engineering, Detail Design, Procurement, Construction, and Commissioning phases is meaningless as they are not synchronized across engineering disciplines. For example, control and instrumentation Detail Design is frequently executed when the process equipment Procurement is already finished.

The figures above may lull the reader into thinking that CE should be a hot topic today when nearly 50% of all capital projects are behind schedule and 90% late on the documentation handover. Quite the contrary. LinkedIn CE forums are more dead than alive (April 18, 2017).

Searching LinkedIn for "Concurrent Engineering" gives no results. Obviously, there should be some major insurmountable challenge of CE implementation silencing the voices of the CE proponents.
From my experience it is

Wrong biased assessment of the project schedule activity completion by the project engineers and managers working under the pressure of budget and time.

Biases result in leaking the engineering data with the information status of "preliminary" into designs with the status of "final". Following late discovery of these, leaks trigger massive activities rollback and a waterfall of updates.

The following true story from my past illustrates how CE works in practice. I was asked to give my approval on the purchase of the energy recovery device working under cyclic loads. I approved the purchase under one condition - the order should be signed after getting the cyclic fatigue analysis report from a third party. The project manager upon figuring out that this report would take several weeks to prepare, decided to shorten the device delivery time and signed the order first. Unfortunately, the report was all bad.

By my estimates (6 mega-projects) false or proxy completions increase engineering and detail design workloads by a factor of 3 - 4(!) and narrow the gap between CE and Sequential Engineering.

This challenge - lack of information authenticity and sufficiency validation (IV) - becomes even bigger with a surge of Big Data usage in capital projects.

We mean IV when we talk about the project complexity. It is IV that triggers the bankruptcy of Westinghouse Electric Company, a once-proud name that in years past symbolized America’s supremacy in nuclear power.

How does www.crenger.com - project-plant life cycle management platform - handle IV?

Crenger introduces hundreds of business rules (BR) for validation of the project scope, equipment and subsystems match, engineering solutions applied, etc. Rules act differently; some are "go/no-go", and others are conditional and may change the project execution flow. The beauty of business rules is in their interoperability: they work across all the projects in a predictable manner.

Secondly, Crenger offers an Outstanding Issues Tracking (OIT) framework aimed at the project trifles that eventually make perfection. In the above-mentioned case of the energy recovery device, OIT would have blocked the contract signing.

OIT logs and tracks identified problems and ensures that they are corrected. It periodically reports on problem status and process metrics through email alerts and auto-assigns problems to predefined specialists (e.g. the pump expert). It automatically notifies the assignee of the new assignment and the due date.

BR and OIT, not the project manager, decide when it's time to move to the next activity of the project schedule. In other words, BR and OIT is the first and hardest-to-make step toward decision-making automation.

This path is already beaten by Business Process Management (BPM) - the science and technology on a steep rise.