I found a new soccer study on player injuries that sheds some light on the reason the club should not rush to bring Ben Arfa back on the field:

Ekstrand and his colleagues studied the injuries of about 2,300 players in three European soccer leagues over the years 2001 to 2009.

About one in six players were reinjured, which means a recovery period of up to 30 percent longer than with the first injury.
This can result from "trying to come back from injury too quickly," Brophy said, adding that the study's findings highlight the fact that players and trainers need to make sure players go through adequate rehabilitation before going back on the field.

This helps actually quantify the serious risk of bringing back Ben Arfa too soon - he could have a 1 in 6 chance of re-injuring himself.

For this reason, I fully support Pardew's decision to postpone Ben Arfa's return date at least month from early April to early May:

Newcastle boss Alan Pardew has revealed Hatem Ben Arfa faces a battle to return to first-team action before May as he bids to recover from his double leg break.

He added that the player had "every chance of playing against Wolves" on April 2.

However, Pardew has now said Ben Arfa has little prospect of playing in that game.

"I am going to protect him," he said. "I can't just throw him in. The Wolves game sounds optimistic, even though I'm sure, in his own mind, he has set that as his target.

"He is still very much in the process of recovery and has a long road back. It may even take us into May. To break both bones in the shin is tough - not just physically, but mentally, too."