I was always taught to leave at least a little slack in the stabilizers, because over the range of motion of the lift arms, the distance along the stabilizer will vary (ultimately depends on the linkage layout compared to the arc of the lift arms). If you make the stabilizers perfectly snug at one position, they could bind when the lift arms move to another position. The behavior even changes depending on the width of the implement and how it spaces the lift arms. Basically, anything that affects the two relative arcs that the stabilizers and lift arms make when the lift arms swing through their range will play into this.
You want at least a teeny little slop in the 3-pt linkage over the whole range of motion. Doesn't matter where it comes from, but be careful snugging the stabilizers down too much as then you shift the need for slop to the ball ends of the lift arms and the pins on the implement. What I do, after hooking up an implement, is move it to extremes and make sure it still has a little jiggle.