In the multi-touch example given, the 5-day reporting window does not account for the fact that tomorrow's revenue will be sprinkled into today. That means that your ROI for today's spend isn't final until you're beyond the attribution window.
This can get sticky in things like AdWords where the main UI reports on "date of click" and keeps changing, whereas Search Funnel reports report by "date of conversion."
Fortunately, most bid management platforms like Marin let you make that distinction in reporting.
Date-of-conversion has the different (and in my opinion worse) issue of being 100% accurate in terms of current cost-per-conversion but under-values all marketing channels. This is because it attributes the cost of visits only to conversions that have already happened, while more conversions may later be attributed to those visits. This means that a conversion based model is actually worse for channel analysis.
For example, right now I'm going from a 90 day window for certain goals in AdWords because I know that while the majority convert on that goal in ~30 days, there's a long tail. Unfortunately, Marin restricts their window to 30 days, so any deeper digging will need to occur within Google Analytics or data from our data warehouse.
I'm not sure if this is the same thing as what you cited, as my argument is about the cost association during the reporting window as opposed to the future revenue association. I can't figure out a way to back those out in real-time (i.e. in enough time to make adjustments to the campaign) though.
With a fluency in the ramifications of the attribution models and windows, I like to look at multiple attribution models (last-click and parabolic multi-touch) to draw conclusion about performance.
My takeaway from the post was simply, "Be aware of how much attribution models influence metrics," and I think that's a critical point.