[old_tv_nut]

Thanks. I had a vague memory that color CRTs might have been made a bit narrow to allow longer horizontal retrace time (thus cropping off some of the picture) without distorting the aspect ratio of the picture content. Why longer retrace? To reduce peak pulse voltages in the horizontal output device. I do know that the Motorola solid state sets used extra-long horizontal retrace times for this reason, but have (or had) no sure evidence that the CRTs were made narrower to compensate.

If your numbers are accurate, this is a 4% reduction in trace time; this would allow retrace to increase by about 2 microseconds (20%), which would be significant.

A physical spec sheet for the CRT would settle this.