I disagree. He is known for not playing political games. Stalling for political reasons is not in his playbook (to his credit). He'll keep his word (as is his habit, and to avoid the "apple doesn't fall far from the tree" headlines) and sign it once it hits his desk.
However, even if we are successful at lobbying Congress and preventing this, I will not forgive this reasserted promise. He'll have to do some rather impressive domestic work to overcome this black mark in my book. (at least 4 of the following: ANWR, filibuster beaten, secured borders, budget below $1.8T, killing race-based laws, Dept of Educ eliminated, and/or PBA)