why is this even discussed? at LEAST the very basic of reality must be included. the question is to what extent beyond the basic the manga writer includes it. i'm a firm believer that if Croc fought Eneru, fulgurite or some form of rock would result from the energy clashing with teh sand. i already made an argument for that, and i'll say it again. Oda borrows from reality, as other shounen writers do, quite a lot. a few examples:
1. it's almost common sense that rubber insulates electricity
2. friction does induce heat and energy (sanji's devil leg)
3. metal objects held in high areas would ground lightning (buggy at loguetown)
there's more but you get the picture. anyone who says "OP is it's own world! it doesn't relate to ours, and I don't care about that reality crap!" is a moron, excuse the rudeness.
if Croc fought Eneru, do you think Oda will say "well..lightning clashes with sand, but I don't know what really happens when that happens so I'll just make shit up. i'll make mountains form, volcanoes erupt, and raccoons being born out of the sludge that's a byproduct of the eruptions." you believe that? you believe he wouldn't look up what would happen if he didn't already know, but instead just make shit up?
now before anyone scream, "yea well in real life rubbert would melt from the lightning and you can't jump 50 feet into the air or cut buildings in half with your nose", think a little. it's obvious rubber would melt, it's obvious friction doesn't provide sufficient heat to maintain Sanji's technique. but it's a manga, this is the fictitious side of it. there are also limits to how close he can get to reality before he can't get any closer (or manga wouldn't work). instead of a shounen it'd be a shoujo or something in that case.
1 more thing, there must be limits and rules in a world, and what better limits than ones we already know and can relate to? that's why what i stated as numbered examples works. here's more stuff that are limits
1. blood/wounds; wounds also require time to heal and impairs fighting ability
2. stamina & pain
5. water behaving the way it does, land, sky, sun, moon
6. ships -> ie, can sink, float,requires sails, etc
these are SOME to list. these are the OP realities that are identical (almost) to real reality. if they are sufficiently wounded, they will either faint or die. if the ships have a hole in them, they will sink. get the picture? it does relate to the real world, a huge amount.
i don't agree with what you said at all. the 2 worlds are tied together and relate quite closely in a certain light.