Ok, I totally underatand the intellectual rationale behind the existence of the Source tab in the Effects Control Panel versus the Sequence settings.
Source settings are applied to all instances of any segment of that original clip. So if you change the Source settings in one bit of a clip on one sequence, you've also changed every instance of any bit of that clip on every other sequence in that project.
That's a two-edged sword right there, it can both be very handy ... and very destructive.
But the two biggest problems both have to do with the operational part of dealing with Source vs Sequence settings:
You never ever see every effect applied to any clip in one view. You can't if it's got any Source setting, nor can you tell if it has a Source setting effect. Which all RED, ArriRAW, BMRAW, Canon Log & RAW, Sony Log & Raw, and now several other cameras provide with their media.
You must mouse click to go between Source and Sequence tabs. There are no keyboard shortcuts nor control surface options to get "there" from "here" ... only the mouse.
That second option, the required mouse action, is a killer for those with "advanced workflows" who either run keyboard shortcuts, StreamDecks, or control surfaces and do everything possible to get away from the blame mouse.
I would VASTLY prefer the Source and Sequence effects were ALL shown in the Effects Control Panel, and that Source effects simply present as the "intrinsic" effects do.