Yes, with positive Ackerman, the line not being pulled will develope a bit of slack as it is moved away from neutral; at neutral the lines are just barely taunt. One of the biggest mistakes made in setting up a good pull-pull system is to much tension on the lines when they are at neutral, you want them just snug enough so there is no droop or slack. When pulled and the line not being pulled gets a bit of slack, no harm as the air loads keep things working properly. You will NOT get any adverse results from this slacking off of the unloaded line.