Very glad that you're thinking of this direction. Sending USD fees to a fund (operated by the network) than buying XTS to burn not only helps the security, it also helps to make the bitUSD an asset with dividends which I think is important for the success of bitUSD. I like this idea.
It does not make it an asset with dividends, it just goes from the users' bank account to the DAC's bank account and the market peg will continue to function like it always did.
What it does do is build up some capital inside the DAC which may become like AAPL's cash hoard. This value "on the balance sheet" is still accumulated to BTS X shareholders because for the BitUSD to exist on our balance sheet, someone has tied up 2x the value in collateral somewhere which means it is "out of circulation".
As crazy as it may sound, it actually results in a 2x ROI for BTSX to hold USD reserves rather than sell them. You don't see it in the share supply, but I suspect we could create a "virtual share supply" calculation that calculates the XTS held in collateral for the USD in the fund and "subtract" it from the XTS supply.
It does mean that some shorts will NEVER be able to cover at any price because the USD is "out of circulation". This shouldn't really be a problem, all users are entitled to hold their USD so a short has to increase their bid for USD to get priority.
Boy the economics of this are complex.... holding USD is a bet against XTS, but requires someone else to make an equal and opposite leveraged bet for XTS. The result is the same as increasing the demand for XTS and burning it as dividends in terms of how it should impact the XTS price.