That's precisely why I posted the link to the minifinder. Did you even look at it? In less time than it took for you to rediscover the conventional wisdom that it can't be done, you could've run an experiment yourself. 
When you do get around to it, you'll find that the minifinder, as its name suggests, is stripped down to fit on an 800K floppy, with about 100K left for your other software. It's not a full finder, so you will not get a familiar desktop, etc. However, as I understand your OP, you don't need to run a full system 7. And from your other post, 100K free space is more than enough.
Maybe this won't solve your problem overall, but it's the only way I know of to run a system 7 thing from a single 800K floppy. And naturally Apple's docs will say it can't be done, because what they really mean is that it can't be done with Apple software, and even with third-party software, it doesn't get you a full system 7 desktop.
When you do get around to it, you'll find that the minifinder, as its name suggests, is stripped down to fit on an 800K floppy, with about 100K left for your other software. It's not a full finder, so you will not get a familiar desktop, etc. However, as I understand your OP, you don't need to run a full system 7. And from your other post, 100K free space is more than enough.
Maybe this won't solve your problem overall, but it's the only way I know of to run a system 7 thing from a single 800K floppy. And naturally Apple's docs will say it can't be done, because what they really mean is that it can't be done with Apple software, and even with third-party software, it doesn't get you a full system 7 desktop.