[jampekka]

That depends on whether you accept the risk of having to find another line of work. Depending on the place, you can do almost anything you want even at PhD level. I've been on a chain of grants, doing quite freely what I want, for over a decade. But I accept it may break at any point and then I'll just go do something else.

After PhD there will be nobody telling, and often not even caring, what to do. But that may mean that you don't get your PhD or you don't get another grant to live on. If you get a tenure it almost literally means that you can't be fired even if you do nothing at all. What is surprising is that almost all with tenure keep running the rat race even though they don't really get anything at least material out of it.

(Nitpick: I think serious research is the fun one. The one churned to get another grant is neither serious nor fun.)

[starcraft2wol]

How did you get a position without a postdoc?

> After PhD there will be nobody telling, and often not even caring, what to do.

If you make the hiring cut in you’re in for about 5 years of grunt work and committees as an assistant prof, right?

By “serious research” I mean the one they do for career advancement and hiring.

[jampekka]

> How did you get a position without a postdoc?

I am a postdoc, just have been for quite a while (on four different grants at least). In Finnish academia it's not that uncommon to stay a postdoc even until retirement.

> That’s not true. If you make the hiring cut in you’re in for about 5 years of grunt work as an assistant prof.

For teaching and admin yes. But at least in fields I know, what research you do or whether you do at all is all up to you. Of course the risk is that you'll be unemployed after the assistant prof. term ends. My point is that if you don't care about that, you're quite free to do whatever research-wise.