While I can understand the want for that, there's too much issues. The only reason npm does it this way is because the module that depends on B v1.3 and a modul

While I can understand the want for that, there's too much issues. The only reason npm does it this way is because the module that depends on B v1.3 and a module that depends on B v2.1 could be introducing some really bad bugs or breakage if you force all modules to use B v2.1. That's one of the reason bower is losing out.