The process is not necessarily for rifle "fitting", but rather to let a shooter know how much eye relief is available
for a particular scope. For most new scopes, that can easily be found and the stats they give are normally pretty close from the ones I've checked. I have seen a few scopes that seem only to show the longest eye relief found in a scope's power range, which may or may not matter when mounted.
A scope with too short eye relief for a particular rifle/cartridge combination can still be mounted with "proper" eye relief fit. But
, that "proper" eye relief may not prove to be enough for a hard recoiling rifle, being too short. This is the most prevelant "fudging" I've seen by scope manufacturers. They do not list the proper least
amount of eye relief, which is normally found at the highest power setting. In the case of this new-to-me scope it may well have saved me a case of scope eye (another case...lol).