Imaro
Legend
I thought what I wrote was quite clear, but let me try to elaborate. The PHB gives a different description for Martial Encounter and Daily Powers vs all other power sources.
For Arcane and Divine Encounter Powers, it says this:
These are spells or prayers of such power that they take time to re-form in your mind after you unleash their magical energy.
For Martial Encounter Powers is says this:
They are exploits you've practiced extensively but can only pull off once in a while.
The implication is that is normally impossible for Arcane characters to cast an encounter spell for than once every few minutes or so.
By contrast, the martial encounter power is something the character can attempt as often as he wants (He's practiced it extensively, after all) but can only pull off or use successfully every "once in a while" which in game terms amounts to once per fight. This is a very narrative explanation any way you look at it.
You're adding your own interpretation to it... what if the non-traditional magical energy used in the martial exploit is so strenuous on his body... he literally cannot attempt it again... how is this any less implied than what you are claiming? I think you're reading what you want into it but without any explicit evidence to support your assumptions. Again no reason is given, it's just vaguely stated that one can only pull of an exploit once an encounter/daily... And for the record I'm sure Wizards and warlocks practice with their spells as much as a fighter does with his exploits.
I linked to T.V. tropes because this is a very common archtype across genres. I'm very suprised you are not conciously aware of it. To give some examples...
Batman is not a magical character, but he can accomplish things that are not realistic. He is unrealistcally awesome, but not supernatural.
Conan is not a magical character, but he can accomplish things that are not realistic. He is unrealistcally awesome, but not supernatural.
Odysseus is not a magical character, but he can accomplish things that are not realistic. He is unrealistcally awesome, but not supernatural.
Tarzan is not a magical character, but he can accomplish things that are not realistic. He is unrealistcally awesome, but not supernatural.
Yet there is still scale, and that is what this argument boils down to. According to those tropes there are things Superman can do that Batman never will be able to... no matter how awesome he is. the question is where is that line for D&D? What is the point where the fighter has overstepped his D&D "tropes" and gained those of a wizard, or cleric. The problem is... without actually defining the tropes... this becomes an utterly pointless argument.
D&D Fighters have never been realistic. You cannot realistically and consistantly kill enormous Dragons and Giants with a 3' length of steel. This does not mean D&D fighters have ever been magical, because they aren't, outside of whatever magical gear they have been equipped. They are assumed to overcome unrealistic and impossible odds through strength, cunning, and skill at arms.
Again with "realism"... I'm not arguing about realism. What I'm arguing about is logical consistency. If the realm of controlling things outside of oneself in an indirect manner is considered "magic" (whether traditional or non-traditional... then when someone does this they are performing magic, plain and simple. It's never been about "realism".