Remember, nothing is alleged to--or can have--happened to all of MLB over some one or two seasons: the claim is that PEDs were being used at a slowly but steadily increasing rate (and thus "distorting records") from very roughly 1980 through the present. Were that so, or anything like it, we would expect to see a clear long-term uptrend during this period. But we don't: we see a nearly flat line that, if anything, slopes slightly down. The "boost" just isn't there. But that doesn't seem to stop anyone from talking about it.
Fired cases do not reliably reflect the force with which the primer was struck. Because one print is deeper than another doesn’t necessarily mean the deeper print was caused by a harder hit. (The depth of print in a fired case is not a true indicator of the force of the hit, since on explosion the primer usually mushrooms around the firing pin. In actuality, if there were no explosion, the print would almost always appear much shallower. It will be noted there are exceptions where the primer is flattened out against the breech face by the explosion or does not mushroom around the pin ~ giving the impression of a comparatively light hit. The uniformity of Hornady prints has impressed me because it indicates uniformity in primer quality and consistency of powder charges.)
The Union Association survived for only one season (1884), as did the Players' League (1890), an attempt to return to the National Association structure of a league controlled by the players themselves. Both leagues are considered major leagues by many baseball researchers because of the perceived high caliber of play and the number of star players featured. However, some researchers have disputed the major league status of the Union Association, pointing out that franchises came and went and contending that the St. Louis club, which was deliberately "stacked" by the league's president (who owned that club), was the only club that was anywhere close to major league caliber.