I should point out that by "domain knowledge" I meant the domain of a particular language and/or platform. For example, having a deep understanding of what is

I should point out that by "domain knowledge" I meant the domain of a particular language and/or platform. For example, having a deep understanding of what is available in .Net in C#, or STL + Boost in C++, or CPAN in Perl. Real-world domain knowledge is somewhere between helpful and vital, depending on one's role.