I’m finally getting around to finishing my 400 to 470 stroker. Bottom end has been done for over a year but covid put a bit of a hold on things. I’m a bit of a rookie with this high performance stuff. I’ve read a lot of back and forth about breaking in the engine. I know to use proper break in oil, high zinc, rev up to 2500 for 20min etc. The one thing my old man and I can’t seem to determine is the dual valve spring concept. Can a cam not be broken in with both inner and outer springs set up? Do the inners really have to come out for break in and then put back in for tuning on dyno day? Is this just an overkill myth or is it actually the case? My old man is old school and never remembers going through this on any engine he built back in the day but maybe thoughts have changed on this?