Novel Boiler design?

Thinking hard about how to construct a SIMPLE, yet RELIABLE boiler for my loco, I came up with this design (steam dome, steam line, valves etc. omitted):

I'm not 100% sure that this design, or a similar one, has never been used before, but at least I've not seen it in any of the numerous boiler books I've perused...

Note that this boiler could be used ONLY with propane (or other non-smoking fuel, perhaps oil?) since cleaning the interspersed & crossed convection tubes from soot would be almost impossible, except by removing boiler from loco & dunking in organic solvent...

But, as I see it, this boiler would have several advantages over the "ordinary" type of model loco boiler:

Thanks everybody for the feedback regarding this boiler design. The main opposition seems to be that if any of the crisscross tubes started leaking, I'd have a dud boiler. Well, if the inner assembly is removable, it would be fixable, right? Somebody asked how to de-solder both ends at the same time... So how about adding a "spacer" ring with pull-out "ears" to the tube ends - the ring would be a little thicker than the heating tube protrusions. This ring would be silver soldered in, but would enable me to de-solder the ends one at a time - pulling out the ring, the end would be free, and the other end could be de-soldered later. Do you see any structural hazards? I don't, a silver solder join like this should be really strong.

Also, I've been warned that if the "crown" of this boiler would be even a little exposed, there's a risk of the tube solderings failing and leaking. So, there goes my safety argument - or actually, that is kind of a non-replaceable fusible plug... ;-) Seriously, would flattening the top of the inner tube, while keeping everything else the same, be agood idea? More water space, lower crown. But structurally not as safe? But, all those tubes make excellent stays, right?

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