The size of the file doesn't make much difference. What matters is the resolution and framerate of the vide
For a back-of-the napkin calculation can we not assume that data equal to the entire size of the file will be streamed to the client during playback? I understand that frame rate, etc. are important as well but I do not need exact figures, just a general idea of what size tube** is required on the viewer's side to see the video without skipping.
** The internet is not really made of tubes. Unless you're from Alaska.