The proposal has raised alarms for members of Congress and NASA safety advisers as the agency and SpaceX prepare to launch humans into orbit as early as this year. One watchdog group labeled load-and-go a “potential safety risk.”
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It is a potential safety risk. That’s why there’s an escape system, and the capsule is on top of the stack. It’s a lot safer than the Shuttle.
The original shuttle design had pyrotechnics to separate the crew compartment from the bulk of the orbiter and parachute it safely to earth.
NASA management elected to remove the pyrotechnics and the parachutes.
In the challenger disaster, the crew compartment separated at the designed-in parting line, and the still living crew plummeted without the benefit of parachutes to a very hard impact with the ocean.
I’m not sure that escaping out of an engulfing fireball is worth the effort. Out of a “regular” fire down below, yes, but that’s not the likely outcome of a fuel-loading incident.