While I understand your limitations around technical hiccups, your above argument appears to be escapist. There is equivalent tonne of research that says most investors (super large SWFs to tiny retail) would be better off investing in ETFs instead of a jamboree of investment alternatives currently used. Despite this, there is a healthy and active market for direct investments, advisor / manager fraternity because we all believe we are better than everyone else.
As regards cut off times, all what has been asked for is parity with others. If one were to extend your argument, it should not make a difference to an investor if the cut off time is 9.30 am the day before or 2 days before - except in this case you would have seriously disgruntled customers.
To each his own and if an investor expects a certain cut off time for reasons best known to him, then its a fair ask.