In your opinion what are the most significant contributions in relation to contingency thinking in project management?

Personally I think the main contributions include:

How does that theory impact project management methodologies?

Contingency theory can impact project management methodologies tremendously because this theory is suitable when following occur in project management realm:

Why is that field under explored ?

I'm not sure as haven't done any literature review in this topic. Perhaps someones can share / more if they have done so. Thanks.

Interesting! Following.

OK, normally I do not do this :-) https://xkcd.com/386/

They scientific countering would be: where do you base this bold statement on?

As a practicing project manager and researcher, I do notice a big gap between what is researched and presumed by science and what is actually happening. The use of contingency theory (I presume: 'there is no management style that fits all contexts or situations') is broadly promoted in project management certifications like IPMA, PMP and more. It is in the basic theoretical knowledge and for higher levels (like IPMA B), it is even assessed whether the practitioner can show specific situations of adapting management style to the context. {scientific remark: it is questionable whether the assessors or the PM can actually prove or know whether the used management style was indeed appropriate}.

The CT impacts methods in such a way that most methods seem to be fairly rigid in their approach. Even Scrum has very fixed prescribed ways of working, like Prince2. Believers in such methods will claim that their method is fit for every occassion/project. Most practitioners will however be very flexible in their usages of those methods (see several publications on hybrid methods). Some even found that some projects 'claiming' to use a rigid method were more agile than projects claiming to us an agile method (http://resolver.tudelft.nl/uuid:2a85960e-e164-4f9b-af8a-733837a6aeb9).

One of the problems of project management is sponsorship (see 2010 Arras report), whereas sponsors or top management prescribe a form of managing the project without knowledge of actual project management processes or needs.

In my opinion there is lots of research on adapting project management processes, tools and/or management style to the situation (e.g. Bessner and Hobbs or Zwikael on tools, Koops on trust, etc.) only not named contingency theory or situational management. It is not underexplored, it just happens to be not named as you expected it to be. Adapt your search strategy (pun intended).

Some of the papers I read which mention "contingency theory" (15% of the papers in my personal Mendeley database) seem to use this as a kind of disclaimer. On the other hand, it's certainly a lens a critical observer must use. E.g. Müller: "... contingency theory explains the reciprocal determination of OPM elements (i.e., their positing against each other) by ... "

I perform research on ideal characteristics of members of project steering committees. Based on papers the ideal characteristics might vary on a lot of contingencies (project phase, complexity, degree of outsourcing, level of projectification etc). I will have the same issue as the other papers. I might be able to add one of two independent variables in the research. But more would make at least the quantitative part undoable.

I am not sure that the field is underexplored. Just that due to practical reasons only a few variables will be taken into account in at least quantitative studies. Could you explain with what you mean by "underexplored"? And what is "the field" or is it more a lens for research?

For me in my practitioner life what contingency theory brings: if you state there is one best solution, you should be very carefull in proving that.