No two LCs will do the exact same thing. I can use his scenario in how we did LC.
We didnt speed clear or aim to be the server best. We just wanted to get gear to those who would benefit the raid the most. Using his scenario, assuming theyre all coming from prebis trinkets, then the bis trinket would hold the same gain over what it would replace. Mage 1 who got the trinket, in theory, should do even more during lust with both bis, so he would be the obvious choice. A faster kill is a higher dps for everyone as theres less rot coming down from burst to sustained dps.
We didnt hand out loot till the end, specifically because of things like this. So revamp the scenario a bit, if only 2nd bis trinket drops, then its going to mage 1. If both trinkets drop, mage 1 gets bis and mage 2 gets second. Our LC also believed in getting loot out to people in as even as we could distribution. We know that at best getting scraps and at worst getting nothing week after week can be demoralizing.
For scenario two, despite the warrior getting a bigger gain, those two dps are not equal. A smaller gain for the dk versus the warrior on a personal dps level, but the dk getting the trinket provides a bigger raid dps gain than the warrior. The dk should get it.
Just a former LC members take on it since you said you wanted to understand the thought process.
It’s good when it’s biased towards non trash players. That’s why they go play in ms/os or dkp guilds and the good players get “bias” towards them because they are better than the bads lol.