cahn

I mean, my big complaint about grad school at the time was that it was too easy and they needed to raise several standards

Yeeeeah my grad school experience was very different from yours, in the sense that those words do not compute for me? Like, it would not occur to me to rank grad school as "too easy" or "too hard" or anywhere on that axis (and I don't think I ever heard anyone else do that either); it was about doing research, and the research was always both too easy and too hard, because if it was easy you weren't working on a problem that was hard enough and so you obviously should be doing the harder problem, but if it was hard you weren't making any progress so it meant you had to simplify the problem to something you could actually do. (The old joke is, if a mathematician can solve it, it's "trivial.") I can recall only once in my grad school career where everything came together and I was actually solving things in a way that wasn't too easy or too hard, though that once was glorious. (I suspect this is a difference between hard science and other fields, because it does occur to me that I don't think I would have felt that way about doing a Ph.D. in Medieval Welsh lit. I would have had other different issues, mind you, but not that particular one.) And then of course in grad school, once one is doing research, this is the start of comparing not just to one's class cohort but comparing one's research to all the other research that's ever been done by anyone, and most people are bound to come off a bit poorly in that comparison :)

There were classes too, I guess, but no one really took those seriously, and I guess there were qualifying exam standards in my program as well, which no one really paid attention to except as annoying hurdles that had to be overcome to get to the real part of grad school (or, if one decided one didn't want to do that, to take the consolation master's). (I do think the exam standards were pretty reasonable; I failed one of the exams the first time because I got cocky, and I knew at least one person who failed out totally, but they were designed to be passable if one studied, and not if one didn't, and not as "weed-out" exams as some other places use them.)

But, like, research-always-being-too-hard-and-too-easy is physics academia in general; I don't imagine that changes between grad school and being a professor. The parts of physics grad school that would be drastically better as a tenured professor (or for that matter not being in academia):

a) not knowing where one's money was coming from - I fortunately had a fellowship and didn't have to worry so much about this, but that wasn't the case across the board
b) being very much subject to the vagaries of one's advisor (of course, this varied greatly from advisor to advisor, and was generally much more of an issue in lab environments because of the way labs work (the two professors in the above story had associated labs) -- my (non-lab) advisor was extremely hands-off, others were not; my institution tended to be pretty reasonable in general, but let's just say that I heard stories about extreme control-freak advisors not at my institution)
c) not having very much money -- which was fine at the time as a young single person without expenses but I certainly very much like making more money
d) knowing that one's life was going to be uprooted every couple of years or so if one stayed in academia
e) being at the bottom of the academia pecking order (again, generally worse for lab students as this means they had to do all the lab grunt work)
f) often having all the grunt work of grading/etc. for a class, without having any of the control of the class or fun parts of teaching (I didn't have a TA-ship so not my problem, but a constant complaint)
g) worrying one isn't good enough to make it in academia (not everyone worries about this -- there is some evidence my advisor never did -- and I suppose that tenured professors at the top of their field also maybe feel this way to a certain extent, buuuuut there's a lot more evidence that the answer is "yes" at this point)

So, basically, the same kinds of lack of money/power/autonomy/control that, presumably, also to a certain extent characterized Diocletan and Maximian under Aurelian (especially in AU). Now, I fondly remember grad school and had a lot of fun and am glad I went, and as is somewhat clear from the above I had some reasons why I had a pretty good deal, and also the lack of responsibility that comes along with the lack of money/power/autonomy was a large part of that, and part of me would say "those were the days!" -- but when I think about it rationally, I wouldn't really want to do it again now. :P

All that to say, I could understand Maximian (even if he normally doesn't miss the old days) being struck by a sudden gust of nostalgia -- and even more so, in the world of the fic, Theodora seizing inspiration from hearing Maximian tell stories about "the olden days when..." :)