I don't want to derail the topic other than to say I see both sides of this discussion. I am a test engineer and daily I work with NIST traceable instrumentation (Nation Institute of Standards and Technology) which means the values measured by these devices can then be traced all the way to the original standard. Many of these standards have been converted from tangible objects to a fundamental constant of nature. If anyone is curious read about the international Prototype Kilogram or IPK. The only reason I am responding to this thread is that I find the conversation very interesting and enjoyable to read as each party has a valid point. I am only just starting to use CCS and can see the usefulness for my own needs. Topics like this that stay friendly and allow for a candid discussion are very helpful for people new to the system such as myself. Seeing the perspective of multiple parties helps to highlight concepts of CCS that I need to gain confidence in to be able to explain well to others. "If you can't explain it simply, you don't understand it well enough." (Einstein) I find instrumentation and measurements fascinating and the history of them as well. Just remember it matters not what you hang from the end of your rods my friends, if it has a measurable mass then whatever unit you use to describe that mass it is converted from "The Kilogram"

Tom, please humor me. How do I measure ERN? I know how to measure IP, but not ERN.

Pretty simple. Use the required number of pennies to properly load the rod, count the pennies and correspond that to the ERN figure just as the article specifies.

So it's exactly like you're doing with IP ("Intrinsic Power" is another term coined by Dr. Hanneman). In that case you are using something to load the rod, converting it to a weight figure, and stating that as IP.

If you continue to believe that Dr. Hanneman was in error, you could contact him and petition him to correct/change his system.

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I did not ever say that I thought D. Hanneman had made any error. His system is brilliant and I use it effectively all the time. I am simply pointing out that to state that one "measures ERN" is untrue and confusing. One measures Intrinsic Power. IP is then converted to ERN using the Rosetta Stone.

ERN is a number created by Dr. Hanneman to relate the power or the rod to the weight of a fly line according to AFTMA standard line weights. If the Rosetta Stone says your rod has an ERN of 5.5, it will cast an AFTMA compliant 5 weight line well. According to Dr. Hanneman. I have no reason to doubt that he is right.

But ERN actually has no value for rods other than fly rods. We could talk, measure, and compare rod power and action angle forever on cast and spin rods and have no need for ERN. It is a convenient derivative of IP that is useful for fly rods. There is no problem in using it for any rod, but it is NOT a measured characteristic of a blank or rod. If it were it would have units and we could have a scale designed to measure it directly. But we cannot. We need the Rosetta Stone Chart to determine it. It is this relationship between IP and ERN that I believe many find confusing because they have not read the whole set of articles on CCS. Your simplified CCS system would be even simpler and easier to understand for builders and users of non-fly rods if ERN never existed. There would be no Rosetta Stone. No conversion.

By keeping it for these rods keeps us using a single, consistent, system of objective rod description for ALL blanks/rods, which is good. Learn for one type of rod, you've learned it for all.

The amount of weight required to deflect the rod to the required amount to take the measurement, is neither indicative of the amount of weight/load it can handle nor the amount of weight it is suited to cast. It's simply what you use to put the rod into the position needed for taking the measurements. And to be accurate, Dr. Hanneman originally used IP to relate rod power to fly line weight. So he had IP but decided not to use that form as the relative power figure - for that he chose ERN for all the reasons I've previously specified.

So ERN, as Dr. Hanneman has stated many times, is a relative power figure. It works for all rods and remains relative across the entire spectrum. If it didn't, we wouldn't have ERN figures that go up well beyond 100. I've never seen a fly line listed beyond about a 12-weight. Of no value for anything other than fly rods? I fail to understand that comment. I can assure you that a rod with an ERN of 100 is less powerful than a rod with an ERN of 125. The relativity of the numbers doesn't change at an ERN of 12.

Like you, I think things are better if you have one single term for relative power. ERN being the term that Dr. Hanneman coined for that purpose, it's not up to me to say that everyone must change and use IP from this point forward.

The Common Cents System uses AA for Action, ERN for Power, and CCF for Speed. The Defined Bending Index, which Dr. Hanneman suggested be inscribed on every rod, calls for AA and ERN. But you can use whatever you want. If you want to put IP on your rods, you are free to do so.

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Like Mick, I also believe that Dr. Hannemann’s CCS Concept was brilliant. However, I know that an IP weight (in pennies, grams, grains, or even ounces) is more useful to me because no conversion to ERN is required. Because of this I will continue to use iP to describe the power of blanks I use. With all due respect for everyone involved in this educating discussion I totally understand all arguments made, and for me the use of IP is just a matter of ease, convenience and relevance.
Norm