This is one of the best articles I've read describing a doomer perspective on Peak Oil.
He even references Wittgenstein!
Speed; Severity; Duration.
My take is: speed depends entirely upon the sanity of the US administration, and whether it attacks Iran. Assuming that they do, I think a decline in oil supplies will hit very quickly afterwards - so, within a year or two, max.
Severity: rapid, 8% or more, with all the consequences thereto.
So maybe I am a doomer? Unlike this writer, I think some form of domestic living comparable to what we have now is possible. What we won't have is personal cars.