There is a world of difference between the stock cam lobes and springs of the flat-tappet era and the ultra-high acceleration lobes and big springs of today. Even the 30-year-old "chevy lobes" found on many high performance cams of the 70s were really mild in comparison.
So you have to be really careful breaking in a new high intensity cam.

One thing that always makes me wonder, it is easy to say use weaker springs but where do you get weaker springs for a 0.545" lift camshaft?

R.