[20100thibault]

I think this is good case of Black Swan (it would be highly improbable the same problem hit all the companies in a diversified portfolio but could happen a la hearthbleed). There's an extremely insightful book written on the subject (the black swan by Mr Taleb). Wich I do recommend.

Discounted cashflow = bullshit used to rationalize the sale price ( it can have some use in super long term predictable business like real estate with 10 year lease and well diversified tenants)

Hope this was helpfull