Ok, here’s the revised version of the method in the OP:
Each rift gets split up, into:
Regular time. Time spent fighting mobs. This scales up 17% per tier.
Move time. Time spent just moving around, without really fighting any mobs. Assessed either by video or at 60 seconds, or 20% of total time, whichever is higher. This does not scale up at all.
Stricken time, assuming this gem is used. Time spent fighting the boss. Assessed either by video or as an average amount of time for a boss fight, for the build in question. (Leapquake- 180-300 seconds. Frenzy- 60-90 seconds. Etc.)
Conduit time. Time with an active Conduit. Always 60 seconds, assuming FoT is used. Use if presence of a Conduit is known/suspected. This scales up at a rate of (Conduit time / (Conduit time + Regular time) * 17%). In a 5 minute rift with three minutes of Regular time, and a Conduit, this would be (60 / (180 + 60) * 17%), or 4.25%, per tier.
Using these time scalings, adjust the original total time upward to see how many additional tiers might be reachable.
If video is present, it can be inspected for instances where increased incoming damage might kill the player, increasing the time. If there is no video, the top 30% of the increased tier expectation is treated as a range. For instance, if we previously said “+7 tiers”, we now would say “+ 5-7 tiers”.
If Squirt’s is used in a way intended to maintain high uptime (using a shielding mechanism such as Gizzard, Fortress Ballista, etc) then video can be inspected for instances when the Squirt’s buff might drop due to higher incoming damage. If no video is present, another 30% of the “solid” potential becomes a range. For instance, our “+ 7” which became “+ 5-7” now becomes “+ 4-7 tiers”.
And that’s it. This may not provide us with a perfect, absolute answer, but I do think it will allow us to look at timing in a significantly clearer way than we have up until now.
Any interest in trying out this method, in whatever fashion you see fit?