By definition the relationship:

Work = Duration x Effort  is in error, this creates too many limits and makes it difficult if not impossible to deal with different production rates for available resources that can do the same work but at different rates.

Effort does not necessarilly yields productive work and therefore must be dealt using separate metrics.

The article is a perpetuation of how bad is MS Project at dealing with the issue.

The correct relationship is:

Work = Duration X Production Rate

The production rate metrics has been in use by decades within the construction industry to the point all estimating references use the concept of production rate in a transparent way.

It is easy to see the error [horror] by looking at the units on the formula:

Work = Duration x Effort
Work = hours x hours   or hours**2, does not make sense.

On the other hand if you use the correct formula

Work = Duration X Production Rate
     = hours x Volume of Work / hour
     = Volume of Work,  this makes all sense.

MSP and P6 might be acceptable for IT jobs but for construction jobs does not meet the expectations of many of us. I still have my doubts about how these software handle the different productivity of different software coders the same way different excavators have different production rates for the same work.

When working using more advanced software if an IT activity have no units of measure you simply use 100 for amount of work and % for unit of work.  In this way the production rates for different coders can be expressed as %/hour.

Very simple and transparent, the problem is that for MSP and P6 implement the concept the software must be completely re-vamped therefore they will continue insisting on limited tweaking methods to do what would otherwise be easy and transparent.