For one thing, New England is notorious among fantasy circles for having one of the most unpredictable backfields in the league next to Mike Shanahan's Washington Redskins.
The argument to be made against this statement is the fact former Patriots rusher BenJarvus Green-Ellis had 24 touchdowns from 2010 to 2011. The problem was, his owners never knew when those TDs would come.
In 2011 for example, the Law Firm went five weeks between his fifth and sixth scores of the year. While Bolden and Green-Ellis aren't the same running back, not only does the former have to fight against the unpredictable Patriots offense, he's not even the starter at his position.
Before his 137-yard, 16-carry performance against the Buffalo Bills, Bolden had just seven total carries for 15 yards this season. He had no carries against the Cardinals, just two against the Ravens and the remaining came Week 1 in a blowout victory over the Titans.
Judging by the numbers, it appears Bolden's most notable performances have come during games the Pats had well in hand. While New England is a talented team, it's not going to blow out teams by a score of 52-28 every week.
That means fewer carries for Bolden during the close ones, kind of like what should be expected when Peyton Manning comes back to Gillette Stadium in Week 5.
There's reason to be excited about Bolden's performance, sure. Just remember that in that same Buffalo game, starter Stevan Ridley had 106 yards and two touchdowns. Bolden didn't outperform Ridley by a great margin, which means he likely didn't create much separation in the eyes of head coach Bill Belichick.
Bolden told the Associated Press (via The Washington Post): "You go into every week of practice, going in and trying to learn as much of the game plan as you can. Because In case your number does get called, you have the opportunity to go execute everything."
He did that against the Bills last week, but the trouble with him in fantasy is that you never know if—or how many times—his number will be called each week.
Given his Week 4 performance, Bolden warrants keeping an eye on by all fantasy managers in all formats, but that's all for now. Managers that ran out to grab him after his big game shouldn't talk themselves into starting him until the Patriots' backfield picture is a bit more clear.