Older shows/commercials fit round sets better

[wa2ise]

The TV studios have specially marked monitors (old days markings on the CRT glass, nowadays electronically generated) to show typical overscan of consumer TV sets (rectangle), and another smaller rectangle marking showing the area every TV owner is sure to be able to see. In the early days, they probably also showed the typical truncated rectangle one sees with a roundie set. Obviously important that the product and company logo be seen in that commercial. Today with fast forward VCRs they will want that logo to be there for a long period of time so the VCR user will still see that logo (so the advertiser still gets an impression on the VCR user.