This topic has interested me for a while. I know people--myself included--that trade far fewer days and make far fewer trades, and make a great deal of money and do this on a full-time basis with no other personal source of income. Even though a multitude of trades aren't executed on a daily basis, one still needs to monitor (this is still work) the market all week from open to close. So, what is substantial? I think that if you show a consistent profit, the IRS will leave you alone--no matter what entity you use or how much you trade. I trade futures options, so I automatically have the advantage of MTM accounting and the 60/40 rule--this is IRS law. Only disadvantage is that I cannot get a full writeoff of all my business expenses (limited by Schedule A) nor can I apply a yearly loss all at once (limit is $3K per year).
I was thinking of an idea. I can create a management company that will manage my personal account. This management company will meet NFA/CFTC regs. The management company can write off all business expenses. I will write a personal check to the management company that will incidentally cover the expenses. This check is the management company's sales per schedule C. The management company appears to have no profit. Then, on my schedule A, I will enter the amount paid to the management company. Of course the write off will be limited, but it is higher than it would be otherwise. Even if I have a loss in my trading, I can still write a personal check to the management company as before to zero out my business expenses. I can still report that amount on my schedule A, and I can deduct up to $3k of capital losses on my 1040. If anyone sees a flaw here, I appreciate any constructive criticism.