It's an interesting hypothesis and one that has crossed my mind. Like yourself, I have no evidence to suggest one way or the other if what you suggest is true. As most people know, explaining how loot works are from October 2017 and before looter professions were introduced. It's interesting; Mindark never told us the impact of looter professions on TT returns. It speculates that the impact of weapons' efficiency on TT returns may have been nerfed to accommodate the looter professions. Due to it being difficult to test such minor percentage changes in loot, hopefully, Mindark will provide us with an exact explanation of looter professions and whether its introduction changed how weapon efficiency worked.
Let me share something interesting about efficiency I have not shared, lol; this might interest a few nerds of Entropia, but here goes anyway. MA stated that efficiency couldn't go any higher than 7% on TT, with 100% being the max efficiency, but they said they were uncapped with looter skills.
With Loot 2:0 weapons no longer having a linear DPP/efficiency path, it gave MA the ability to give players a higher DPP weapon (exponentially reducing the cost to play) without interfering too much on how much loot could be extracted and at the same time avoiding most TT surplus liabilities.
An example is the
Unique Sacrificial Dagger,
3.8 DPP but has an efficiency rating of
94%, translating to a
6.58% TT returned over the games base return rate. Interestingly, the DPP should make this weapon over 100% efficiency using the old linear method; what do I mean? Let me explain a little more.
Using the linear method, any in-game item with a
base DPP of 3.62832 DPP would be 100% efficiency. Though there are equal or higher DPP's values than the one mentioned, the latest weapons have below 94% efficiency, means efficiency was already nerfed before looter professions, IMHO.
When the looter professions got introduced, MA used this mechanic to give people the urge to skill up because looter buff isn't capped, unlike efficiency, it can go 0.07% per level unlimited, so TT surplus is possible for the diehard players (Messi91) but takes place with Looter and not Efficiency.