Sorry if I'm being a bit offensive, I respect your work a lot, but it's actually just my job to look for a flaws/inconsistencies/lack of integrity in other people analysis/expectation/whatever (and outright exploit it, but this is another matter) so I used to question numbers in a very strict way.
I just want to discuss, investigate, clarify and get to some sort of mutual understanding.
We see from separate console US performance that most "popular/mainstream" consoles(PS2, GC, Wii) peak out on 3rd year and more "developing" consoles (PS1, OG Xbox) peak on 4th years. Gen7 is an exception though, but it peak much later than expected, not much earlier. The only ones that peak yearly are those that clearly lost competion and even though they do not start to visinly decline immediately, instead they struggle for some time.
Looking at current situation - we have roughly the same Q1 YoY and I expect some price drop for PS4 this year to keep momentum in-line with historical dynamics (either popular or developing). Xbox One will hold or at least will have small drop (which is what every struggle console do as they tend to resort to drastic measures). WiiU can't actually provide a feeding fodder as it's already has a very low baseline (and actually sale better than last year). It's not just clear what will cause sales to be roughly the same as last year. (you have 16.2 in projected shipments this year versus 15.5 sell through number last year, mere 4.5% increase)
And this is just US market - the most "developed" one and thus least dependent on price decrease. Overall situation should be even more favorable to later peak.Your current dynamics propose that console market will be saturated in developed countries on it's second year, which is quite abnormal from historical data.