I presume by 'understanding an area' you mean being familiar with established abstract models of that area? I think that often in practical conditions the abstract models are not the area under work. They are the mapping of the area to some formal system. And that the 'area' under question - whatever it may be - can be mapped to an infinite amount of formal systems. For lots of practical purposes, there is some 'obvious' algebra of a thing one wants to do - in these instances all that is needed is an individual who can map the problem to any logically coherent structure, even just a private one in their head, and a willingness to solve the problem - and great stuff can ne done without a literature review. Sometimes the establishes models are really, really good since they either simplify a messy looking problem and/or point out to some not so obvious aspects of a system at which point an expert in the field can have an advantage over the clever layman. I think sometimes the knowledge of existing formal models can make a person blind to certain facets of the system they are working with.

Also, if one approaches a thing by a burning desire just to implement one single thing on top of it they will probably have an internal model that is very much focused on the problem they are solving.This practical need can induce them to create a new formal model or just sidestep lots of non-issues that would be a burden to deal with.