Hughes Whiplash Camshaft

I had been talking to Doug via PM on the other site about cam selection for my engine just before the fire, he never did answer my last PM though I am assuming he read it as it isnt in my "outbox" any more. I have 2 PMs out to other members there (about different topics than what I was talking to Doug about) that are older than that last PM to Doug but still in the "outbox" meaning as yet unread by the other end.

After I found out about the fire, I didn't press the issue of Doug not getting back to that last PM, I figured he had bigger fish to fry.
I thought I was locked in on a good cam choice for the rest of my combo, and was asking Doug of his thoughts and he suggested the reverse pattern cam. That last PM that is as yet unresponded to, was about the how different my engine will run with all else being equal between his RV10 and his RV15.... In the beginning I was asking his opinion of the Oregon cam 819, and he suggested "his" cam. but my engine is not destined for an A body, but rather, a D150. I pretty much have the rest of my combo ironed out besides the cam. I have heard it said that an engine can run quite different with all else being equal, but choosing a given cam over another "similar appearing" one. and Doug kinda went that direction with my idea of an oregon 819 for my build....as I remember something about his cams being a known quantity/quality.... to put something "close" in, my engine might run radically different from what I am after.
I will admit, cam profiles do nothing but confuse me. I dont get the difference in duration vs duration at 50, vs advertised duration, etc...
and wouldnt the "centerline" be the "centerline" under any conditions? I don't get the (for example) "ground on 108* centerline, installed at 112* wouldn't that mean that on the "other side" would only be 104*? (averages out to 108) and taking that 108 as an example, that 108 is the # of degrees between the max lift of the intake vs the max lift of the exhaust?

I remember back in the 80s when "Super Shops" was all the rage, and they carried Erson products extensively. Cams, springs, timing components, valve covers, all Erson/ who we hear nothing from these days. I remember my 1st 318 rebuild, and looking back now what I remember of the cam I picked out compared to what I see today, it appears that it was pretty close to a 340 stock replacement. the rest of the build was a basic re ring, all stock. and that motor was all noise, no go. it seemed worse than that engine had been stock, before teardown. it was my "guinea pig" engine in jr. college auto shop. Ever since I have been very leery of cam choice.
One of the best 318s I built was a stock (unrebuilt) bottom end, with a stock Melling 360-2 bbl cam in it// with a Magnum engine top end// and the 1.6 ratio of the magnum engines. topped with a plain Edelbrock Performer (not "RPM") and an Edelbrock 625. I don't want to make the same "super shops" mistake I made with cam choice back then with this engine. But I want better than stock.

Sorry for the thread jack, but the ideals I put forth here do seem to apply to some of what the OP was asking about..... if not adding a "What NOT to do".