One way he be might doing this while not sacrificing substance is if he's the head of a very large group. If you have 20 postdocs and 40 grad students, that wouldn't be a crazy number of papers over five years. Alternatively, he might be highly collaborative - if he's usually not the last author, he might just be farming out computational/mathematics staff to projects that need those skillsets (which frankly would be awful for the careers of those mentees, but it would explain what you're seeing).

That said, two papers a month is setting off my bullshit alarms - I'd take a hard look at those papers and just see if he's solving real problems or not.

> yet could we discuss what’s happening there, if anything?

Without actual details, there’s nothing to really discuss. Surely you can look up some of his papers and read them, right?

Usually people churning out papers aren’t writing anything substantial in most of them. Could be plagiarizing other papers, in which case you could probably figure it out with some targeted searching.

But it should go without saying that he’s probably not actually making a breakthrough every other week like clockwork. If he brags about volume of publishing first but not really about what he’s studying, you probably have your answer.

In some fields, the boss mandates to have their name on every paper published in their organization, even if they are not involved in the research, or even if they do no research at all.

For example it looks the (in)famous Didier Raoult was cited as author (on average) in publications at least every three days in the last 10 years:

https://pubmed.ncbi.nlm.nih.gov/?term=Raoult+Didier+marseill...

Varies a lot by field.

Eg, in some parts of public health research and medicine you get your name on a paper by being the source of the data, whether you do any work or not.

Alternatively, you might put your name on everything any grad student in your lab produces.

There are also field-specific effects which push numbers up or down: it is easy to publish in medicine since there are so many journals and many do not have high standards (some do, but many do more).

In good journals in economics it is not uncommon for papers to spend years in the referee process so total publication numbers are low. (Bad journals in economics have much lower standards.)

Paper factories aside, it can be very field dependent. I knew mathematical physicists who struggled to write more than a few papers a year because they chose to chase closed form solutions for their problems (also already had tenure). I also knew organic chemists who would take a molecule, swapped an methyl for a ethyl and write a paper about the new molecule. Voila: 24 papers a year