Evidence That H-1B Holders Don't Replace US Workers

Okian Warrior writes: In response to Donald Trump's allegations that H1B visas drive Americans out of jobs, The Huffington Post points to this study which refutes that claim. From the study: "But the data show that over the last decade, as businesses have requested more H-1Bs, they also expanded jobs for Americans." This seems to fly in the face of reason, consensus opinion, and numerous anecdotal reports. Is this report accurate? Have we been concerned over nothing these past few years? Remember, this is about aggregates, rather than whether some specific job has been replaced.