Hi!
relied on unless there's a guarantee certain set of data (e.g. all observatories) have the same accuracy and it is kept up-to-date.Like in all the wiki-world, this should be guaranteed through the reference claim, shouldn't it?
No, reference only says where the data comes from, best case - when it was retrieved (vast majority now doesn't have that either). But no guarantee it is still true with claimed precision.
I can't think of anything really useful right now... What I'm afraid of is creating fake grids like it happened in DBpedia with too much rounding (see [1], p. 44/45). Maybe with 1 m precision it won't happen today, but it might in the future for very POI-dense areas.. (might it?)
Thanks for the link! Indeed, if the precision is too low, there is danger, but from what I understood (my Czech is kinda weak ;) the grids there are also because of some data representation artifact.