'Invicta' goes up slightly left directing crack. Climbers usually descent by using a tree on the left where the obvious crack ends. However, the route can be continued further up to the top over the slab on the right. The new bolt in question is added on this slab which cannot be otherwise protected. Someone correct if I'm wrong with this.
In that case, it sounds sensible. I think I know where it is - but perhaps they have done an entirely new "alternative finish"? I wonder if it the same grade?
I find scary natural routes inspiring, but in a case of 'Käkimassaa', I do understand the bolting. In practise the route cannot be naturally protected and most probably it hasn't seen any repetitions. Nikko's first ascent is exceptional, but a climbable route in this case is probably better than a curiosity. There isn't that much potential left in Jaanankallio and the line (or face) offers some nice climbing.
I think Käkimassaa is the one route at Jaanankallio below 6 that I haven't led (I even done both Paskaränni and Grande Couloir in the past, and "enjoyed" the offwidths of Paskan Marjat a couple of weeks ago), as basically its too bold for me. So from a personal point of view I can enjoy it now, but I'm in two minds over whether it was a good thing or not as Finland has very few really bold routes at any grade.