I have been walking in a pair of Teva shoes for the last 18 months. These are goretex lined, have suede leather uppers and a vibram sole. I have found them to be pretty comfortable and robust for the walks I have done.
Recently, I have noticed they are not as comfortable as they used to be. In particular, they seem to be getting smaller. The first indication was when my little toenail on one foot would be sore after a trip. Now, the nail is all black and I suspect I shall soon lose it.
The second thing I have noticed in the last week is that my second toe is now pushing against the end of the shoe. Needless to say, this is not comfortable for anything more than a few minutes.
I suspect that what has happened is that the leather has been thoroughly wet several times, and as it has dried out, the leather has hardened and stiffened, maybe shrunk. No, I did not bother treating it to keep it supple

So my question is whether the shoes are beyond recovery, or whether if I dose them with dubbin or something they will soften and the shoe will go back to its former size.
Any ideas?
(Problem is that I am in Europe and planning to start an 18 day walk in about a week and need to decide whether to try to recover these shoes, or to look for something else to wear.)
Cheers
David