The "scroll", the unending page of HTML, not "broken" up into fixed pages.
Could this be mimicked by manipulating the
\pdfpageheight, a pdfTeX primitive and
\vsize to set the length of the text, and the page it figures on as a single page including the full length of the text.
Memory limits TeX/pdfTeX limits, viewer limits?
Setting the viewer padding between pages to 0pt would then give the appearance of an "HTML" page, the better id as to browsing a longer text on screen. PDF on screen where most of the searching and associative reading is done waists a considerable percentage of vertical real estate.
Preserving the advantages of the pdf format. A single long page would reserve the off-line viewing, on screen, without any disadvantage.
Generally text for printing and viewing on screen has different requirements anyhow, many other aspects, colors, papersize (printed book formats are multiple, for one, so a source manipulation is mostly required regardless when 'for printing' is meant).
Currently the PDF output and underneath the eventual pdfTeXed source is solved on a per physical dimensions basis, at least near exact geometry of the screen meant to be used, say 16-9 proportionality for most laptop-desktops, so a browsing on page per page is possible. That of course depends not only on the processing of pdf but also on the viewer interplay.
pdfTeX should have more precise instructions possibilities (as conditionals relative to geometry and size to advise the viewer how to output the pdf). XeTeX and LuaTeX are not more finegrained as far as we know.
Ultimately the biggest advantage of PDF is to control how to present the sum of text and graphics and pictures, (audio and video are gadgets mostly), as compared to HTML, where pages are modulated and manipulated with anything by any intermediate interference. Secondly html is almost never a "contained" single file as a PDF file is.
The concept of pages, a separation of pages and the algorithms of TeX and pdfTeX operating and taking into account pages ... waists quite some real estate onscreen. Just a conceptual ruminance, that inspired the question of whether it is technically even feasible to do anything different.
Part of the solution of course is to have a physical monitor that allows for twisting it long side up. It is then that the ordinary pdf (a4), zoomed to convenience shows how much space is wasted. Foot-lines, indexes, title pages, blank pages, that have their reasoned functionality in print, to scan a book, to orient, anotate etc. have little when viewing is on-screen. On screen, and anybody else has probably different modes and techniques, a simple "/ regexed-string" would walk to the appropriate places one is looking for faster and after a possible second or third ajusting of the regeluar expression one should be unbeaten in efficiency per file. So PDF needs links, pdftex calls them "all sorts of annotations", and that should have prevalence when not printing but on screen purpose is meant.
Academia is mostly done searching, and manipulating digital data, no serious research can longer be done based on mostly analog sources. The time frames and the human processor capacity is simply dwarfed as to the variables.
Above to partly justify my question on the technicalities of pdfTeX/XeTeX/LuaTeX to have any justification.
The question repeated: are "very" long pages, a single page per file possible in pdfTeX?