h) +20% dig speed stacks linearly and not exponentially (I don't think anyone knows whether this is correct)
I think we know enough about WZI to conclude that it is actually exponential and not linear.
From this:
Each modifier is multiplied in succession. For example, two 20% discounts would be: 1.0 - 0.8 * 0.8 = 36%
Including Digging Speed (from Modifiers) where +50% Phase 4 Faster Digging speed & +10% Hard China digging speed rewards combine to total 55% speed reduction, all the other "reducers" operate exponentially, so it makes sense that SAsc dig reward would too. Certainly, 5x +20% dig speed yielding 100% increase speed (instant completion) simply doesn't jive with the WZI meta, which is increasing benefits are linear/summative, and reductive benefits exponential, or differently worded: whichever benefits the player the least (;
So it would end up being:
- 1x SAsc benefit -20% dig time = -20% reduced dig time (80% dig speed)
- 2x SAsc benefit -20% dig time = -36% reduced dig time (64% dig speed)
- 3x SAsc benefit -20% dig time = -49% reduced dig time (51% dig speed)
- 4x SAsc benefit -20% dig time = -59% reduced dig time (41% dig speed)
- 5x SAsc benefit -20% dig time = -68% reduced dig time (33% dig speed)
- 6x SAsc benefit -20% dig time = -74% reduced dig time (26% dig speed)
- 7x SAsc benefit -20% dig time = -79% reduced dig time (21% dig speed)
So the benefits of increased digging speed diminish with each additional SAsc. However ... adding +50% digging speed or the +10% from Hard China would bring further reductions (but also exponential).
I suspect this doesn't vastly change the analysis graemes has provided, other than maybe change the 'break even' point from ~2 years to 2.1, 2.2 or 2.3 years. Not a huge difference.
@MJZ, That's fairly impressive clear times to get the 2nd SASc - have you actually done 2nd SAsc yet or still digging? Actually nvm, I see from the "Leaderboard" thread that you've done 2, working on #3. Here has done 3.