What's the problem with Bill Clinton?

The NYT has this somewhat puzzling report about Bill Clinton's role in the Hillary campaign. We're told that the crowds at his New Hampshire events are "sleepy and sometimes smallish crowds" and that he's seemed "determined to lower his wattage, to eliminate any hint that he might be the headliner." What's going on?

Mr. Clinton’s practiced self-deflation on the stump reflects something of a split within the campaign over how best to use him, campaign advisers say. There is a feeling among one faction that he was overexposed in Iowa, and that his presence became a distraction.

But he can't be willing the crowds to be smaller than the auditoriums where he deigns to appear.