oh i understand this and maybe so but like i said it's personal choices when people buy their Trucks, Ive owned both auto and manual and manual transmissions suit me and my needs and haven't let me down.
Saggs... Ive pushed started many diesel trucks in my 25 years operating trucks and equipment, on the Cummings diesel the Pump has a manual override knob, just turn it and bump the truck forward it will start, A pure mechanical diesel engine unlike a gas engine does not need an electrical spark for ignition. On a gas engine all you have to do is take away the electricity and the engine can't run. A diesel uses the heat of compression to ignite the fuel so removing the electricity from a diesel may not stop it from running.
There are of course, exceptions to this. All modern diesel engines use some electrical devices to operate. Almost all diesels have an electrically operated fuel shutoff solenoid and electric fuel lift pumps. Others like the turbo diesels use an electronic injection pump. As long as these engines are getting air, fuel and electricity they will continue to run. Cutting off the electricity to these engines should stop them. One exception would be a normally aspirated diesel with a malfunctioning fuel shutoff valve.

You've had a reading comprehension fail.
I've worked on engines all my life, I don't need a lesson on how a diesel works, I grew up on the farm fixing diesel tractors, pickups, bailwagons, and generators many times.. and now I fix airplanes

Read my post again and comprehend... Try starting a diesel on a cold day with no battery and no external power and let me know how that works out for you?
You can push start a gas engine with no battery because the alternator can provide enough amperage to get the ignition coil going just from the initial crank. However glow plugs and manifold heaters get really, really hot, which takes a lot of current over at least 3-4 seconds. A spinning alternator from a rolling truck can't cut it. With a dead battery on a diesel you will have no preheat at all. Not a problem really if you live in Texas of Arizona, but in any temperate to cold climate a diesel with no preheat ain't gonna start, unless you use a whole bunch of ether which will cause a bunch of other problems over time.
I'll take your word on push starting a diesel, I've never been desperate enough to try it, no doubt you can't just pop the clutch like with a gas though, like I said it's a whole lot harder to crank 20:1 compression then 8:1.
I've had the privilege of operating a 96 Powerstroke that the glow plug controller went out on, even at 80° F, it wouldn't start. With 2 big batteries it'll crank for a long, long time too, won't do any good with cold cylinders though. If I gave it 3-4 long shots of ether then it would start rough, but like I said that not healthy at all.