The Z4000 can output 12A for several seconds before any form of shutdown happens.
If the picture I posted wasn't enough of a reason to get smarter and use a breaker- you kind of deserve what happens next. You've been told- stop coming up with reasons to avoid it.
Basically, Bob- You, yes YOU are the reason you need a breaker.
Doesn't matter the transformer, it matters that YOU will be running trains, mistakes happen, derailments happen, and I could cite all day long the number of things that won't take 12A shorted without burning up.
GET THE HINT.