Tip Drill: Important fantasy PSA, for those about to trade...

Oh, hey, look what crept up on us...

BOOM. "Trade End Date: November 14, 2014." Friday.

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That's right, your trade deadline has arrived in most Yahoo leagues. Very soon, you'll have no opportunity to improve your roster except via the waiver wire. So if you have glaring lineup needs to fill, you'll want to act now. Today. Time to get to work.

But before you hit the trade market, it's my responsibility as a fantasy guru to provide you with a few pieces of general advice. (We take an oath; this is an inviolable responsibility.) Here are three guiding principles for those about to deal...

1. As we get deeper into the fantasy season, roster depth becomes much less important.

Depth is incredibly meaningful in September — when we have a full season of byes and injuries ahead — but it means next to nothin' in December.

In the final weeks of your season, you simply want the best possible starting roster. Right now, with only 3-4 weeks remaining before the fantasy postseason, ideally you'll trade to improve your active lineup. This is the time to swing a 2-for-1 trade. Today is when you want to flip Watkins and West for Demaryius, or Ellington and Evans for DeMarco. Sure, it's nice to have one solid replacement option on your bench at WR or RB, but you certainly don't need three or four.

At this late stage, you'd really like to deal depth for stars. Use your bench for handcuffs. Use it to stash players who might otherwise be starting for your opponents. Use it to carry a second defense, if you're playing matchups in the final weeks.

2. Deal from areas of surplus to address areas of weakness.

Duh. Obviously. You shouldn't need an expert to tell you this.

And yet still, at this point in the season, I hear from plenty of gamers who seem more interested in winning a trade (which isn't a real win at all) than in winning league titles. This of course is insane. It's entirely acceptable to take a small loss on a deal in order to improve your starting lineup for the most important weeks of the fantasy season.

Let's say, hypothetically, that somehow you owned Julio, Jordy and Antonio Brown in a league in which you could only start two wideouts. And let's also say that in this league, your starting QB was Eli Manning -- perhaps you lost Foles to injury. If that were my situation, I would jump all over a Brown-for-Stafford deal (or something similar). You might consider that a loss in terms of the relative value of the players involved, but your active roster will have unquestionably improved.

3. If you're planning for the end-game, then you better know your playoff matchups.

OK, so it was no accident that I mentioned Matthew Stafford above. His Lions face a stellar schedule for fantasy purposes, during the most important weeks on the fantasy calendar. Let's take a quick look at the end-of-schedules for the NFL's most user-friendly defenses:

Each of the eight defenses listed above currently ranks among the league's bottom-12 in terms of points and yards-allowed. We have ten weeks of data in the books, and these Ds have been the most generous. In all likelihood, they will continue to hemorrhage yards and points. Some are a bit more RB-friendly (Car, Oak, Ten, NY) and some are particularly passer-friendly (Jac, Chi, TB, Atl). But none of them are good.

You'll notice (because red font) that Detroit and New Orleans each have three ridiculously great matchups in the most critical weeks. Stafford and Megatron will face Chicago in Week 13, then again in Week 16. (Related: Add the Lions defense, if possible.) Drew Brees' fantasy season will conclude with Carolina, then Chicago, then Atlanta. It almost seems unfair.

So if you're dealing in the days ahead — and c'mon, that's half the fun in this enterprise — maybe use the grid above as a guide. Trade while you can, before it's forbidden.