I would be doing exactly that.

Or rather I'd merely be right clicking on a URL and my environment would already know I wanted to retrieve that URL as text. If I was in Acme it would open that text in a new window, if in the shell it would just print it on stdout (if that's what I had set up).

When I say the environment knows, actually a program called "the plumber" does text matching on the strings it is sent and executes commands based upon the pattern. I could arrange for different commands to execute based upon the URL.

If I knew I was going to experiment I would be keeping a record.

As Tesla said in response to Edison's now famous "1% inspiration, 99% perspiration" remark

"If you thought a bit more, you wouldn't have to sweat so much."

(both were in a live radio debate, curiously only Edison's has entered the lexicon)

But you do have command history, it's just not in your shell, because the shell is the not right place to put it. The windowing system exposes all the history as a text file, so you can use scripts that use this text file or write your own. I already mentioned " and "" in another comment. In particular, to reexecute previous command I'd just type "".

As for using text editors. Yes, in Plan 9 this is actually feasible and it's a widely used idiom. What makes it so much easier is that I can just middle-click or middle-swipe on anything inside the editor, and it would execute. So yeah, I can just type commands and edit them. When I B2 on them they will run.

Please see this excellent introduction to acme by Russ Cox: http://research.swtch.com/acme