You might ask your doctor specifically what he had in mind??

Instinctively I can see it, having spent most of my college years with doctors telling me to "just stay off" my knee rather than rehab it, which in those days was pretty much unheard of. On a narrow staircase (two hand support) I could go up and down to my fourth-floor dorm room without ever putting weight on my bad knee. Single sided support (wider staircases) meant both legs got at least some use. With two poles, you almost have to use them for support, unweighting both legs - the alternative is to carry the poles sideways! With one, you'll switch it hand to hand, for balance only.

Glad you're continuing to heal.