"In conclusion, bullets with similar shapes and construction materials will utilize the same data. And, above all else, work up your loads by starting with the beginning load and increase charges in small increments, at all times watching for case head pressure signs and stiff extraction."
Actually Hodgen is talking about interchanging bullets specifically, not a generalized concept of all components. And then they add the standard disclaimer to start at beginning loads. Imo, they are basing this on the significant increase of all copper bullets in most calibers. Not so long ago, not many manufacturers had all copper bullets.
Every handloader i ever communicated with had to interchange components based on what they had. Usually with the standard caveat to start low and work up. The same caveat used even if you are using the exact same components. Am very doubtful any of the loads i am using are an exact replica of any manual. Either the case, primer brand, primer strength, bullet, seating depth or firearm used is different.
And will add to the chorus to use a chronograph, especially if going for full power loads in rifle or pistol.
I'm fairly new at this having just started in 1977 at age 12, so I won't bother arguing with many of the reloading "experts".
That said, nothing in that Hodgdon link is particularly "new", and the last paragraph says it all - start low and work up.
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One of the mistakes I most often see are hand loaders taking a nominal charge weight for a powder and assuming it's an exact charge weight. When it comes to a max load, it's only exact for that exact lot of powder and those precise components. Even then chamber, throat, leade and bore dimensional differences can move pressure one way or the other.
Now…that's not to say I don't make substitutions of primers and cases, and bullets of similar weight and construction, I do that all the time. But I work up to the intended velocity and or max load.
I also use a chronograph as both quality assurance, but also to verify that the velocity achieved is in line with the velocity expected, using experience to factor in the effects of barrel length, primer substitution, etc.
However, I also work up to a max load or desired velocity when switching powder lots. Remember that "nominal charge weight"comment? Take a look at a manual that has data in the same chart for powder pairs like Win 296 / H-110, or Win 231 / HP-38, powders that Hodgdon has stated are the exact same powders just with different labels. You'll see different max loads in the data, sometimes as much as a half grain apart because the powders used to develop the data came from two different powder lots.
That's why every load manual publisher will include a disclaimer to either start 10% below maximum, or to start with the lowest load and work up.
It gets even worse when some military cartridge expert stumbles on nominal load data for a military cartridge, like US military M80 Ball. Here's an example I found in about 30 seconds of googling:
"46gr WC846
As per TM43-0001-27"
It's an official US army tech manual so it must be right? Only if you're a moron and don't understand the concept of a nominal charge weight.
The actual acceptance specifications are instead based on measured velocity and other criteria:
- a 146gr bullet (also a nominal weight as 146, 147 149 and 150 grain projectiles have been used by different manufacturers);
- a nominal velocity of 2750 fps in the 22" test barrel, measured at 78 feet from the muzzle;
- the average velocity can not vary more than +/-30 fps from the 2750 fps nominal velocity;
- the standard deviation shall not exceed 32 fps; and
- a mean radius accuracy standard that must be achieved for at least two of three 30 shot groups fired per lot of ammo that equates to 1.59 MOA out of the test barrel.
More importantLy WC846 is a very wide powder specification that encompasses not only WC846 but the narrow end of the specification designated WC844 for M193 ball ammo, where tighter specs were needed to get the minimum velocity without exceeding the already increased pressure limits.
What manufacturers do when using a bulk powder like WC846 where the variation is much greater than the canister grade powders used in hand loading is to work up a load for that specific lot of powder (usually 10,000 pounds).
Yet some internet expert will buy himself an 8 pound keg of surplus WC846 (or worse a keg of "pull down" surplus powder that is inevitably a mix of all sorts of different WC846 lots with Lord only knows what burn characteristics) and proceeds to load exactly 46 grains of it under his 146-150 gr FMJ bullet.
And the best part is you can't explain the potential issues to him, because he's an authoritarian who read it in an official tech manual. More often than not he will absolutely reject any information that doesn't conform to his preferred view of things.
When he eventually bends an op rod or has similar problems with the load, he'll rationalize it or project the fault onto something or someone other than himself.
There's way to much of that going around these days, and not nearly enough commence sense, critical thinking, logic, or observation and scientific method.
eek: gasp) substituted shotgun primers and hull brand in rough times to keep shooting trap, skeet, sporting. Again, well under maximums. 
