EGR apparently was a truly unique blend .
This is the way most of these codger blends are/were, actually. It's funny because most people just say "Ehh they're drug store burley blends, all the same."
In my experience most of the blends today are far more similar to each other than any of the old school blends. Why? Because many of the old school blends were essentially made of the same exact tobaccos so the only differentiating factor they had was their topping... therefore many were extremely unique and even patented (In the case of my Middleton's Cherry). I've tried basically every clone and they don't come even close because their solution is "make stock burley blend and coat with FDA Cherry Flavor #5"... Middleton's wasn't just some stock cherry flavor.. some say it isn't even really cherry at all and I tend to agree with them. It's more a flavoring that tastes similar to certain aromas of cherry.
Yet another important distinction between a company like Sutliff vs. a boutique blender like Peretti... Sutliff had the power and resources to either A) track down and buy the proprietary recipe outright or B) utilize their staff food flavor scientists to blend toppings out of base chemicals that would match it to a high degree of similarity based on trial and error. They also had the machinery to make sure the cut of the raw tobaccos was just right. Etc. Etc.
A place like Peretti on the other hand... they work with stock flavors and stock tobaccos. They can blend whatever tobacco they have on hand to make the basic leaf proportions similar and then look up flavor note descriptions saying "light fruit/plum note" and say welp, let's try some 'FDA standard plum flavor' mixed with 'FDA standard mixed fruit flavor' and hope for the best.
Now when it comes to coming up with 50 different kinds of aromatic blends or like C&D 4,578 different blends all with the same 3 or 4 tobaccos just in slightly different proportions, no problem lol. But when it comes down to nailing a proprietary topping that was developed with chemical technology 50-150 years old... It's just a completely different methodology and set of resources.