Re: IBM 3800 maxed out at 12,423 lines per minute, not 20,000
As someone old enough to have actually worked on the development team for the IBM 3800 printer, I can confirm that the original model was rated at 12,000 lines per minute.
One my memories was that we used laundry bins to catch the output from early versions, before the burster-trimmer-stacker (BTS) was developed. The continuous paper would fly in an arc for several feet before landing in the basket.