Or just for fun try the following, reverse logic using an activity to represent lag.

I do not see any negative lag link! If you can easily work around it then the rule is useless.

Plus:  http://www.ronwinterconsulting.com/DCMA_14-Point_Assessment.pdf

LOL

Emily,

Thanks for the response.

From DCMA-EA PAM 200.1, Earned Value Management System (EVMS) Program Analysis Pamphlet (PAP), October 2012, page 28:

"4.0 14 POINT SCHEDULE METRICS FOR IMS (PROJECT/OPEN PLAN, ETC.) ANALYSIS....These metrics provide the analyst with a framework for asking educated questions and performing follow-up research. The identification of a “red” metric is not in and of itself synonymous with failure but rather an indicator or a catalyst to dig deeper in the analysis for understanding the reason for the situation. Consequently, correction of that metric is not necessarily required, but it should be understood."

From DEPARTMENT OF ENERGY MA-63, Earned Value Management System (EVMS) and Project Analysis Standard Operating Procedure (EPASOP), March 12, 2014, page 10:

"3.2 ANALYSIS PLAN STEP 2: ASSESS SCHEDULE HEALTH....[Two references used for this section are the portion of DCMA’s Program Analysis Pamphlet section 4.0 and the GAO (Government Accountability Office) Scheduling Best Practices May 2012 exposure draft. Note that until the GAO Schedule Assessment Guide is issued as ‘final’ following resolution of public comments, it is not recommended as a primary reference.]....The following metrics provide the analyst with a framework for asking educated questions and performing follow-up research. The identification of a triggered metric is not in and of itself synonymous with failure but rather an indicator or a catalyst to dig deeper in the analysis for understanding the reason for the situation. Consequently, correction of that metric is not necessarily required but it should be understood.

...3.2.2 LEADS ....The reason for using leads should be documented and have proper justification (preferably in a 'notes' column of the schedule.)" -

Note that the more recent DOE standard actually anticipates the presence of (justified) leads.

Nowhere do these standards forbid anything.  They do, however, assume and require that the auditor not be an automaton or an idiot.  That requirement may not be met easily, and clearly your guidance is based on that.  I suppose I may be crediting the auditors/analysts with more competence than they demonstrate in practice.

Yes, a good article.  One minor quibble:

1. To suggest that "DCMA lead criteria forbids the use of negative lag" gives more weight to the criteria than it deserves.  IIRC, the underlying DCMA guidance document suggests that any negative lags need to be discussed and justified, not forbidden absolutely.  The tendancy to turn the DCMA's "target" or "threshold" values (whatever they are actually called) into strict pass/fail limits is a significant issue among non-professionals.  I would rather not see TenSix Consulting among them.

I've encountered many routine situations where a small negative lag (i.e. less than 10-20% of either activity duration) best represents the real overlap between activities.  Forcing the scheduler to add needless detail or (even worse) changing a reasonable FS-1d to SS+9d just to avoid this "forbidden" case would be folly.  Just my two cents.....