I think this would work best as a humorous story, then I can see enjoying it-given that his premise reminds me of Xanth.
On first reading the premise I sort of saw a serious treatment, somewhere in between Chalker's Flux and Anchor and Lyndon Hardy's Secret of the 6th Magic.
I probably should have mentioned the tone of the Short Story & the following Novel I'm doing next month for NanoWriMo is light-hearted fun that doesn't take itself too seriously.
I haven't read Xanth, but I will see about checking it out. Hitchhiker's and Snow Crash are the main influences on the style and tone I'm aiming for. That is, exaggeration for effect and an in-your-face narration style.
But, I personally like to have some solid grounding in truth, but at some point you just have to relax and go for the laugh.
Neuro cringing notwithstanding, I did end up redesigning what I had in mind for the Giant and came up with a better explanation than, "It works because I say so.". I took a nod from an article on Deep Sea Giantism and came up with motive system using a Gravtiy bubble. It at least gives it some logic.
Followed up on what Breandan said and there IS a naval gun, well several naval guns and train guns from WWI & WWII actually, with the exact same characteristics as the gun I had imagined. Exact same muzzle velocity as a Dragonuv...but a range of 30km. I'll have to add in some description, but I have data, hard data as to exactly what such a thing does. Though it was just never intended to be used in this fashion...
