I link to that site several times in the blog post – but I also explicitly point out that the DOS version is _not_ freeware.
There is no such thing as Corel 1-2-3 and never was. IBM owns Lotus 1-2-3. It too is not free and never was, but you can run AsEasyAs for nothing.
It's a complete DOS spreadsheet in its own right, and a very good one at that. Quattro is the spreadsheet that introduced the feature of highlighting a range, then dragging the corner of the range and the program extrapolates the data and fills in the extra cells -- a very handy function indeed IMHO.
There were a bunch of DOS spreadsheets -- Lotus 1-2-3 was _the_ killer app that led the IBM PC to greatness and created the modern computer industry. VisiCalc for the Apple ][ created spreadsheets and improved the lives of tens of thousands of accountants and executives, but 1-2-3 took that concept and made it far more powerful. The name denotes that it integrates the three key functions of [1] spreadsheeting, [2] generating charts, and [3] building and querying simple databases.
IMHO probably the best value commercial spreadsheet for DOS was Computer Associates' Supercalc 5, which was $49 at the end of its life and a very capable, fully-3D program.
And of course there was Microsoft Multiplan, later combined with Microsoft Chart and wrapped in a GUI to create Microsoft's pioneering first Mac app, called Excel.
But if you knew 1-2-3, then AsEasyAs was a direct copy and the subject of a copy-and-feel lawsuit at the time. It's officially discontinued but as it was shareware it was always free to download and use, and it still is today.
Borland Software Craftsmanship: A New Look at Process, Quality and Productivity [1994] https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.12...
Abstract
The Borland Quattro Pro for Windows (QPW) development is one of the most remarkable organizations, processes, and development cultures we have encountered in the AT&T Bell Laboratories Pasteur process research project. The project assimilated requirements, completed design and implementation of 1 million lines of code, and completed testing in 31 months. Coding was done by no more than eight people at a time, which means that individual coding productivity was higher than 1000 lines of code per staff-week. The project capitalized on its small size by centering development activities around daily meetings where architecture, design, and interface issues were socialized. Quality assurance and project management roles were central to the development sociology, in contrast to the developer-centric software production most often observed in our studies of AT&T telecommunications software. Analyses of the development process are ‘‘off the charts’’ relative to most other processes we have studied.
Sadly, I've not yet worked at an org quite this competent, functional, productive. Looking back, it seems this was the high water mark for methodologies, maturity models, software quality assurance, etc.