GRF Spec extension impedance mismatch In no particular order * not many devs familiar with grf spec * so designing and reviewing can be hard * some of the requests are misguided * interacting with newgrf authors can involve blah blah politics * but sometimes multiple misguided requests point the way to one solid spec extension * nobody writes nfo any more, so very few grf devs actually understand the action0/1/2/3 spec, even less 6/7/9/D * nml is easy to patch, but the inertia of having both patched openttd and patched nml is high * maintaining wiki docs without fragmenting wiki docs :( * getting test grfs is a PITA (see 'nobody writes nfo any more') * testing some grf features requires savegames, but these break frequently due to openttd / grf changes