Ouch. This seriously hurts. I currently pay 70K miles to fly SFO-FRA-NRT-BKK-HKG (as an example) on LH F and TG F all the way through. Which is pretty awesome because I'm essentially paying 10K miles to upgrade from C to F (since it's 60K in C).
As painful as this is, and for me it halves the value of miles, we have been spoiled for a long time. It honestly makes no sense for F to be just 10K more than C on that route.
Unfortunately I was getting a great deal until now. I won't be getting it going forward. The balance of the value exchange has been altered, and ultimately we each have to determine whether it's changed enough to change our flying patterns.
And really, hands up anyone who didn't expect this to happen?