@malte

I suspect that it will either be ineffective or that it will be so slow that the process will be qualitatively different. Only experiment will show.

Failure to germinate could be either failure to impact the layer or because of inactivation of the seed by penetration. An alternative reliable method applied afterwards would confirm which of those.

I am just suspicious of the idea that increasing the contact time would achieve equivalence.

@malte

I think way more complicated than that. The key is to degrade the tough outer shell in some way. My understanding is that active anti-germination compounds are at the very surface and relatively easily reduced to an ineffective concentration by repeated washing.

If they are (also?) embedded in the outer cuticle, then the physical degredation of the cuticle would remove them.

Aside from inhibitors, the role of the hard cuticle is primarily to exclude water, to maintain stasis.

Rapid degredation of the cuticle with strong acid would achieve that.

Extended exposure to weak acid, rather than 'taking longer' might permeate over an extended period and literally pickle the seed, making it unviable.