Anna Tingley If you purchase an independently reviewed product or service through a link on our website, Variety may receive an affiliate commission. A new ad campaign for Blake Lively’s non-alcoholic mixers company Betty Buzz stars an unexpected expert to attest to its unparalleled “fizziness”: biomechanical engineer, Dr. Irving Scher, who made a name for himself as a witness in Gwyneth Paltrow’s ski incident trial last month.