It's also completely possible that the check for a portal stone target is processed before the details of the destination room are checked but after the transport flags of the source room are checked. That would display everything we've been able to observe, and it would be a natural symptom of the current functionality being a result of patch jobs to individual spells.
Produce an actual log of a gate opening in an ocean room, ardith.
Quote:
You utter the words, 'oahz'.
A magical gate materializes in a blinding flash of energy.
A circle of stones
The depth of the ocean here is less than the height of a
~~~~~~~ halfling. Whenever the waves calm, it is actually possible to
~~~*~~~ wade along the solid rocky ridge that once linked the island to
~~~~~~~ the mainland. It's raining lightly, very hot, and windy.
Obvious exits: n e s w nw ne sw se gate
A magical gate glowing with red energy leads elsewhere.
A set of rune-inscribed stones is half-submerged in the water here.
A flying monkey exits out of a magical gate.
You start to pray.
You utter the words, 'oahz'.
It's not possible to create a gate here.
Obviously, "Is the target a stone? If yes, open gate." is evaluated before "Is destination room a viable target? If no, fail" but after "Is source room a viable target? If no, fail." It's an understandable situation if you wanted to code the gate spell as nested conditionals. This would explain why you can gate to the above stones, but not to anyone standing right next to them.
This would all go to suggest that ocean rooms do, in fact, allow transport. The transportation is what does not allow them. This would perfectly confirm that voodoo is possible if it hasn't also been given the code to look for what gate and summon fail out at finding. This would also mean that you can get anti-hoarding hours by standing around free from gate and summon in the deep ocean where even scrying wouldn't clearly reveal you. A sad situation.
If we were refactoring the code, I would probably frame this as the need for a well-scoped pathing test. SK predates the proliferation of TDD: I wouldn't say this is anyone's particular fault.