Another alternative method is single-use http. For this video it can be found on this page;
Code:
http://www.c-span.org/assets/player/ajax-player.php?os=android&html5=program&id=353152
The http string is quite long, like this expired example;
Code:
h..p://d19cp144waw2mw.cloudfront.net/trimmed/full/320/320130-3/320130-3-MP4-STD_01.mp4?Policy=eyJTdGF0ZW1lbnQiOlt7IlJlc291cmNlIjoiaHR0cDovL2QxOWNwMTQ0d2F3Mm13LmNsb3VkZnJvbnQubmV0L3RyaW1tZWQvZnVsbC8zMjAvMzIwMTMwLTMvMzIwMTMwLTMtTVA0LVNURF8wMS5tcDQiLCJDb25kaXRpb24iOnsiRGF0ZUxlc3NUaGFuIjp7IkFXUzpFcG9jaFRpbWUiOjE0MDM3NDQxODZ9LCJJcEFkZHJlc3MiOnsiQVdTOlNvdXJjZUlwIjoiOTcuMTE3LjE5NC43MiJ9fX1dfQ__&Key-Pair-Id=APKAIHKVWBEAXX562G7Q&Signature=NQRGyKPr8KbcgRbHrX2ukV3Lny1bfJg23AKheM8Ey4vU9O1pWM13ZbULaqt~HVnRj6yvOngGV8kwayoPNIJpxAAlDzaLLSYi-6AYqyGQ7XRVNmZllFMVijillBaadXeji2q9O~0-XVi0XK~hX49H1zsdoRU8kQ1BbX4h1P8grK0_
You can also turn up this single-use http url by temporarily disabling flash (which enables html5 video on the page), or by using youtube-dl.