I don’t think Medium could become any less transparent on how compensation is calculated than they are under the outgoing system. (I wrote a pair of articles on that a few months back, in fact.) The new system probably is better at gauging actual engagement, but there are always ways to try to game it.
I say “try” because it’s not so easy as you might think. The outgoing system, for example, doesn’t use absolute numbers of claps. A portion of a member’s fee is used to pay writers, divided up according to how that member claps. Say two members each read 10 stories. Member A gives each story 1 clap. Member B gives each story 50 claps. Does member B provide greater income to those 10 stories than member A? Nope. It’s exactly the same, because they both paid the same membership fee and their contribution to writer income is divided up in exactly the same way: equally among the 10 stories. So lots of claps does not necessarily translate into lots of income.
The same will be true under the new system. Lots of minutes spent reading will not necessarily translate into lots of income, because a big component of income will be the fees paid by reading members divided up proportionally based on the time they spend reading each story.
Myself, I’m hoping the new reporting methods will help clarify which of my stories are performing well and which aren’t, so I can (possibly) understand what readers find engaging and what they don’t, which plays into improving my writing. But I’m with you as far as trying to game the system goes. We shouldn’t. The story should be the thing. Do that well, and the income will eventually follow.