my take, & I'm sure the guys on here who have, or still serve will back me (or bollock me if I'm wrong), the yank adage of "train hard/fight easy" can be applied here to a certain extent.
if your day job (emergency services/military) requires you to be able to perform beyond the expectations of normal people, carrying weighty essential equipment, sometimes at speed or in risky situations, then sure, train with appropriate kit to simulate this, in order that when the shit hits the fan, you'll not only cope, but hopefully excel.
BUT if your job is a mundane run of the mill borefest, then don't bother, most gyms, or even our own surroundings have suitable equipment/props that will allow you to achieve what you want, without the risks, & wear & tear associated with carrying unnecessary weight.
these plates are just another fad that will fade in to obscurity in a couple of years, around the same time that a flood of claims hit the press for back injuries etc, think Optigrab in The Jerk lol.
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