You made a lot of good points I didn't make. I should have mentioned I was using examples from Waterhouse and that Brown & Co is similar to Waterhouse in how they handle things. One difference between the three firms you cited and the two I cite is that I don't have to wait for settlement to trade the proceeds of a prior trade at either Waterhouse or Brown & Co. It's good that we emphasize that the day trading rules are by law and should be the same for every firm, while the margin requirements are set by the individual brokerage firms and they have great latitude in their rules about marginability and equity, margin calls and meeting them, even whether to wait for settlement for trading or not. The Day Trading rules are universal -- should be the same at every firm.
I want to tack something onto this post. This is kind of a general alert. You keep your email address in your profile and I wanted to warn you about that. I gave my email address to a member and I've received over a dozen pieces of hate mail, including at least a half dozen with veiled death threats from this person. You never can tell when someone is going to fall over the edge of reason. I think it's a tough problem because you and I too, want to be able to be in touch with people of good intent, and there's a lot to discuss about the stock market and trading it. But there's also risk, and it's very hard to balance wanting to be able to communicate and not wanting to risk our safety. I don't have an answer, but wanted to outline the issue.
Linda