Apples to oranges. A window isn't a stair. So let me ask you an apples to apples question. If the residence has one complying stair, with complying rails and guards, would you allow a second complying stair to be installed with no rails or guards whatsoever? Of course you wouldn't. So why would you allow a second one with noncomplying treads and risers?Also, your statement about not allowing such a violation in a commercial building, but allowing it in a dwelling shows that you acknowledge it as a violation, but you're willing to arbitrarily overlook it; that's a dangerous policy.