It is wrong to use oil to soften leather saddles as this leads to over-softening and stretching. As I remember the advice given on Sheldon's site advocates using Neats-foot oil. While I've used this on saddles in the past I'm aware that as it is organic it does encourage mould. It's also an old-fashioned remedy but that said I have a B17 that is thirty years old and I conditioned it with Neats-foot.

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I don't know if that's bull or not concerning Proofide, it's is something that Brooks advertises and echoed by many people over many years that have had a lot of experience with either selling Brooks or riding on a Brooks. >

Well I'm one of those people that have been riding Brooks for years and have conditioned around sixty or seventy in that time. If you want to waterproof your saddle then I suggest "Hydrophane". This product is used by saddlers and one coat will provide waterproofing without causing the leather to soften too much.
Over this side of the pond we have used these saddles for many, many years and we don't see them as such a big deal.