Questions About Scott 1623 & 1623B First Day Covers

Do you have the count for the special printing of the scored between the 2nd and 3rd rows which was run just for sale at the FD Ceremony City to prepare FDC as well as the few sold via the main philatelic agency location? Or is the count for the special printing run embedded in the counts you mention?

"As a special press run, one should be able to find the impression count of the 1623Bc special print run"

The printing was not special, just the processing. Since they never released figures for any of the later never folded panes, there is no reason to expect figures for this item to be available either.

"While the 1623Bc quantity is small compared to other printed versions, the fact nearly or all of the press run went to collectors helped satisfy collector demand and thus keeps the price (demand) down."

Only the version with the different fold location went to FDC servicers/collectors/dealer. The bulk of the 1623Bc with the normal fold went into normal booklets sold to the public.

There never was a special printing for the "special 2-3 fold panes". Someone at the BEP at some point realised "We do not have panes for fdc servicers" as we would usually provide. So the solutions were:

1. Make no panes for fdcs and reap complaints from fdc servicers.
2. Pull out panes from booklets.
3. Do the "Goebel experiment".
Somebody figured out they could run a piece of half a stamp web roll through the (slightly adapted for this purpose) machine. There is no record who did it, how long the web roll was, and what perforator setup was used (from the observed data we have, it turned out to be the perf 10 setup).

The "Goebel test" proved to be more time consuming/costly/finnicky than simply pulling panes from finished booklets. I don't think anyone has ever tried to guesstimate the fraction of "2-3-fold" panes compared to "normal" panes.

and eventually they figured out there was no reason to have a fold anywhere in panes destined for FDCs

[--By one estimate (Chanove, Jr., 1980a, p.425), only nineteen and a half million total booklets were delivered to the USPS. With one pane per booklet, that means only the same number of total 9¢ Capitol stamps to start with. Mr. Brockert published a slightly lower quantity reportedly announced by the BEP, 18.99 million (1978, p.50). No one knows exactly how many were perf 10, but having lived through those years (for a couple of months, I tried finding booklets in post offices), I doubt anyone thought it was over five percent. Mr. Brockert also repeated a report that indicated only 117,000 perf 10 booklets were made, which he stated might not include the last of production and was likely lower than the actual number. But over a year later (1979c, p.40) he published first-day estimates indicating 172,500 FD items had perf 10's (and 69,708 had perf 11x10½'s). A quantity of 300,000 to one million perf 10 9¢ Capitol stamps total is my resulting estimate. --]
... Chanove, Jr., M. L. Determining Delivery Quantities $1 Vending Machine Booklets, The United States Specialist (USS), August 1980a, Vol. 51 (8), pp.424-425.
... Brockert, J. Perf 10 Mystery: Vending machine booklet slams into philatelic world, Linn's Stamp News, September 18, 1978, p.50.
... Brockert, J. Perf 10 Mystery: Survey yields surprising results, Linn's, Oct. 22, 1979c, p.40.
== from "Field Guide to Postal Uses of the Americana Series"