I suppose Eric Limer (the author of the article) is a battery engineer? Why you guys would take this article as gospel is beyond me. Never charge to full? Stop at 90%? Pure insanity, especially with the 'average' battery life that the Nexus 6 has. This article was basically a conglomeration of well known battery health tips, and anecdotes.
Let's be real, people. If you follow the tips in that article it would only mean that after 3-4 years, your battery might be at 95% of it's original capacity potential, versus 90%. And how many of you plan on rocking the Nexus 6 beyond 2-3 years? I'll tell you how many... next to NONE. If you read and post on these forums, it makes you a cell phone aficionado, and very very few of you will still be on the same phone for 3 years as your only daily driver. You may have an older device you pop your sim into now and then, but I would bet my first born you didn't have newer options as well. As someone posted, if you really are going to keep it beyond 2 years, I would easily put out $50-$80 bucks to have the battery replaced. That would only be for piece of mind that I was back at 100% capacity efficiency.
My point being... top this bad boy off to 100% and get your full 3,200mah charge. You'll be absolutely fine for a few years. This is almost as bad as S4,S5,Note2/3 users who complain that their battery life has dropped after 1+ years of use, when getting back to 100% efficiency is a $12 purchase from Amazon.