In the old days, pitches would start cracking up in the latter half of the Test, so to bat first and pile up a big score was a fail-safe formula. But most of these pitches have been relaid and they are no longer so brittle. Maybe on the fifth day, it can occasionally crumble like it did at the Wankhede when the West Indies last toured India. But, by and large, the pitches just get drier and slower as the match wears on. Whatever life there is in it can be seen at the outset of the match. The moisture in the wicket helps the pacers get some deviation off the seam, and the spinners can get the ball to hurry through, instead of allowing the batsman to easily play anything that's not a half-volley off the backfoot.
Let's see if this pattern is repeated in Kolkata. If the pitch gets easier on the second day, the West Indies might have already done Sachin Tendulkar a big favour in his penultimate Test by opting to bat first.