Realistic, huh?
I prefer the term plausible to realistic. Nothing in the game system is very realistic, but many elements are plausible or less plausible.
My stance is that it's too restrictive to think that the Martial power source can only ever produce 'realistic' results. It's a frigging power source! It's not the absence of a power source. Imho, all power sources tap some supernatural source to allow its users to do stuff that is clearly not realistic.
Yeah, I understand this POV. I just find it totally game mechanics and not reasonable fluff to call what melee types do a "power source". Let's turn them into 4 color comic book superheroes while we are at it.
Let's give them force fields, and teleport, and phasing through walls, and healing, and growing 30 feet, and flying, and invisibility, and walking on water, and breathing underwater, and shooting energy beams out of their eyes, and duplicating into three people.
The other classes have a power source that can do virtually anything mystical or supernatural that one can think of, so the melee types have to have a power source that can do that as well. Uh huh.
There comes a point in time where the mega-anything should be allowed into a power source becomes "less plausible".
I would have prefered a much stricter limitation on what could go into each power source. Right now, it's a bit of a hodge podge. Sometimes its reasonable, sometimes it's just the bigger, better, badder syndrome.