There is definitely momentum towards a negotiated peace agreement, mainly because of the shifting alliances of the US etal. Israel is riding the wave of the regional power's desire to deal with Iran. It is a unique time and Barak won't be the cog in the wheel that will stop progress if progress happens. He will step back or step out of politics again if he goes against the momentum so he won't. He has been put in his place more than once and he will be again.
from the article: In the role of party pooper