Stimulus payments of $2,000 will be a big boost to those that need it, and won’t do any harm to the economy. Most of all, it’s politically savvy. — By Conor Sen Let’s get down to brass tacks: Sending $2,000 in direct payments to Americans is a politically effective but economically inefficient way to provide needed relief to workers and families. When Congress recently approved a new stimulus package, it included $600 cash payments to Americans. But that struck…