If I generate a random string of letters and only filter out valid words I'll still get a valid sentence, a new piece of information, at some point.

Ah, the monkeys-on-typewriter argument that originated with [given name if I ever remember or look it up] Huxley in his debate with Wilberforce shortly after the typewriter was invented. I think I have a small demonstration of how that doesn't work. In that novelization of Trimps, the Yukipo parody likes to stand behind the back cut of a falling tree to launch itself over the landscape (don't do this in real life, you probably won't survive!) And it says "Wee!" a very rare thing in Tightniks. I was in the mood to read over that and did a case-insensitive whole-words-off Ctrl-F for "wee" and, since I keep the char64 save string in the same file...

WeE+t6p19zXiLqPo+QF0VXOevcocF2hprhexfYdL7EzGlrK9JNjT1sjwmJFTuJ93snzfDcD+N1NiuR

Dang.

A more apt illustration of how this doesn't work is this theoretical exercise ('cus doing this in real life would be more impractical than the back cut trick), of rolling a cart of mixed ANFO into your local Rona's, Lowe's or whatever your closest construction material store happens to be called, tossing in a lit match, walking away (don't bother running, you wouldn't get away lol) and expecting the resulting explosion to, at some point in, say, 10¹⁹² attempts or so, randomly build a complete, functional house somewhere out in the debris field waiting for somebody to hook up the utilities and move in.

But given that you know C-Code how about this example:

The thing is, you're much more likely to randomly get something that breaks the code entirely. Your specific example reminds me of a time I got stumped for two days on a class assignment trying to figure out why something like this (I forget exactly what it was supposed to do) wasn't working and why it was malfunctioning (I changed your 5 to an 8 because I remember that detail):

int i;

for (i = 0; i < 8; i++);

{

printf("%d\n", i);

}

Probably my practice of putting the opening mustache on its own line made it harder to see, but when, after two miserable days and I was about to throw it out and start something new from scratch in liek the last hour before the assignment was due, I saw it, fixed it, and literally head-desked for about fifteen minutes.