That's interesting. Do you have any links to more information?
One difficulty I have with that is that even the earliest Christian sources - well before explicit representations of the Crucifixion became conventional in Christianity - manifest belief in the Crucifixion without any indication that they believed it in a different way (
e.g. figuratively rather than literally) than later Christians. Indeed, the earliest Christian text supposed (at least by a majority of scholars, according to earlychristianwritings.com) to have been composed is a now-lost
pre-Markan account of the trial and crucifixion of Jesus, probably composed between AD 30-60 - which, if Mark is any guide, presumably presented the events as historical.