Given the age of projects I've worked on, and that it's unclear whether MSBuild is involved in VS's C++ compilation, I don't think your assumption is correct.
incorrect, the visual studio solution file has build configuration details that msbuild will not honour (e.g. you can specify certain build order parameters), as I found out recently with a project I took over. (I was wondering why building from the command line with ms build produced different results).
That seems like an inaccurate description of what's happening: http://stackoverflow.com/questions/11932164/what-parameters-...
They're using MSBuild, they just don't know it.
Given the age of projects I've worked on, and that it's unclear whether MSBuild is involved in VS's C++ compilation, I don't think your assumption is correct.