No, the 70 years in one year isn't impressive. That's basically 70 comps running 24/7 (what speed etc?). What IS impressive is the fact that the last one was supposed to be the toughest code to break ever...
We want to prove that 70 years of CPU time in 1 year to break the toughest code is impressive:
Let us assume the statement that it is the toughest code to be true, then it follows that rc5-64 is not the toughest competition. Now, lets define rc5 as a project on the open interval of (0, 1,806) (in terms of days). Over 269,467 participants have contributed over the course of 1,086 days. Let us also assume that only 5% of these continue to crack, and have done so for the full time doing a year's worth of CPU time per year each (on average). Thus it follows that there have been at least 13,473 participants, working for ~3 years (of CPU time each on average). In accordance with this, there have been perhaps 40,419 years of CPU time doing RC5. 40,000 years of CPU time while NOT completing what is NOT the toughest code (not even including 9 easier than the toughest ones) is certainly more CPU time than 70 years of CPU time, with less results.
Which is more impressive? 70 years of CPU time in one year, or what they accomplished?
(PS - I know, DES, DES II, DES III, CSC, OGR....but those still haven't accounted for nearly enough time to change the numbers to the point where this would come even close to being as impressive as what the swede did)
End result? (BK == impressed) = 1
(sorry guys....my head is messed up 😛 )