I think if you have a conduit that will sag so much that it would affect your ability to pull wire thru it, you probably would want to rethink your conduit support layout, type specification, or both.
The sag from poor support is one thing that IMO you should rethink your support methods. There is also the cases where you have a gradual curve like when attaching to a "round structure" like a grain silo or some tank, or even an underground run that is not a "straight line".
Those "box offsets" do add up - but you usually have a new "pull point" at each offset, so the only place they are a problem is if you already have 360 degrees of bends between pull points before counting the offsets at the two ends, though many will overlook them and have little additional problem with pulling in those instances, the fourth ninety is usually what is noticed the most once the pull reaches that point:happyyes: