You've lost me. Why would it take more time to check in your dependencies and have the rest of your team get them out of source control? All the package manage

You've lost me. Why would it take more time to check in your dependencies and have the rest of your team get them out of source control? All the package manager would do would be to download them off the internet to the same location. Might as well only have one guy do that once and be done with it. You need to archive them somewhere anyway (to mitigate the issue we're discussing here), so why not keep them in the obvious place?