An apparatus, comprising: (a) an end effector; (b) an elongate shaft, wherein the elongate shaft defines a longitudinal axis, wherein the elongate shaft comprises: (i) a distal end, wherein the end effector is positioned at the distal end of the elongate shaft, (ii) a proximal end, and (iii) an articulation section, wherein the articulation section is operable to deflect at least part of the end effector away from the longitudinal axis; (c) a handle assembly associated with the proximal end of the shaft, wherein the handle assembly comprises: (i) a rotary member having opposing thread regions (181, 182), and (ii) a pair of lead screws (183, 184) engaged with the opposing thread regions (181, 182), such that the lead screws (183, 184) are operable to translate simultaneously in opposite directions in response to rotation of the rotary member; and (d) a pair of articulation control features (162, 172) extending through the elongate shaft, wherein the articulation control features (162, 172) are coupled with the lead screws (183, 184), wherein the articulation control features (162, 172) are further coupled with the articulation section such that the articulation control features (162, 172) are operable to drive articulation of the end effector based on opposing translation of the lead screws (183, 184); and further comprising: a first tensioner gear threadably engaged with a first of the pair of lead screws, such that a longitudinal position of first tensioner gear relative to first lead screw can be adjusted by rotating first tensioner gear relative to first lead screw, and a second tensioner gear threadably engaged with a second of the pair of lead screws, such that a longitudinal position of second tensioner gear relative to second lead screw can be adjusted by rotating second tensioner gear relative to second lead screw. (a) an end effector; (b) an elongate shaft, wherein the elongate shaft defines a longitudinal axis, wherein the elongate shaft comprises: (i) a distal end, wherein the end effector is positioned at the distal end of the elongate shaft, (ii) a proximal end, and (iii) an articulation section, wherein the articulation section is operable to deflect at least part of the end effector away from the longitudinal axis; (i) a distal end, wherein the end effector is positioned at the distal end of the elongate shaft, (ii) a proximal end, and (iii) an articulation section, wherein the articulation section is operable to deflect at least part of the end effector away from the longitudinal axis; (c) a handle assembly associated with the proximal end of the shaft, wherein the handle assembly comprises: (i) a rotary member having opposing thread regions (181, 182), and (ii) a pair of lead screws (183, 184) engaged with the opposing thread regions (181, 182), such that the lead screws (183, 184) are operable to translate simultaneously in opposite directions in response to rotation of the rotary member; and (i) a rotary member having opposing thread regions (181, 182), and (ii) a pair of lead screws (183, 184) engaged with the opposing thread regions (181, 182), such that the lead screws (183, 184) are operable to translate simultaneously in opposite directions in response to rotation of the rotary member; and (d) a pair of articulation control features (162, 172) extending through the elongate shaft, wherein the articulation control features (162, 172) are coupled with the lead screws (183, 184), wherein the articulation control features (162, 172) are further coupled with the articulation section such that the articulation control features (162, 172) are operable to drive articulation of the end effector based on opposing translation of the lead screws (183, 184); and further comprising: a first tensioner gear threadably engaged with a first of the pair of lead screws, such that a longitudinal position of first tensioner gear relative to first lead screw can be adjusted by rotating first tensioner gear relative to first lead screw, and a second tensioner gear threadably engaged with a second of the pair of lead screws, such that a longitudinal position of second tensioner gear relative to second lead screw can be adjusted by rotating second tensioner gear relative to second lead screw. a first tensioner gear threadably engaged with a first of the pair of lead screws, such that a longitudinal position of first tensioner gear relative to first lead screw can be adjusted by rotating first tensioner gear relative to first lead screw, and a second tensioner gear threadably engaged with a second of the pair of lead screws, such that a longitudinal position of second tensioner gear relative to second lead screw can be adjusted by rotating second tensioner gear relative to second lead screw.