There's a lot of disinformation/poor interpretation because in a lot of older American cars, the harmonic damper is also a counterweight, so people call them "harmonic balancers". Well, it's a harmonic damper and it's a balancer. And a floor wax and a dessert topping.
Seems that the more power goes up and the longer the crankshaft/less bearing overlap there is, the more important a good damper is. On Audi I5s the damper attaches to the timing belt pulley, and high HP engines can shatter the OE pulley. Some people blame the use of an impact gun on the bolt, but once you think about the purpose of the damper, the issue becomes clear.
I believe someone posted here that Mazda BP engines will eat oil pumps over 300hp unless a good damper is installed....
