My RF True Fit harness tips (there is repetition here from comments already made):
- Don't re-adjust the harness everytime; get it the appropriate tightness, and leave it alone. The "continuous loop" harness allows you to pull lots of slack out on either side by pulling at the hip area (not the shoulders). Pull harness on one side out, put arm in, pull out other side, put other arm in, even out straps and buckle.
- If you need to tighten, make sure harness is snug around hips then pull down on both harness straps from the back of the seat above metal splitter plate to tighten over shoulders, then pull slack out with harness strap at front of seat.
- Another option to tighten is to release the buckle, give a tug (using above method if necessary), then re-buckle.*
- If you need to loosen, pull up on metal adjuster lever at front of seat (or if this is difficult, push down on the top side of it so it pops up - don't need to reach in as far this way) then pull up on metal splitter plate at back of seat then pull slack out from the front at the shoulders.
- Before you install the seat, shorten the harness straps by putting the splitter plate on the second loop (seat comes with splitter plate on bottom - longest - loop). This helps keep the splitter plate from getting lodged under the seat. Instructions in manual.
Yes, the location of the harness adjuster tab thingy is a major design flaw in this seat. But using the tips above it shouldn't be a problem. You get used to it. And every seat has quirks of some sort.
Here is how to tell if your harness is tight enough:
http://www.car-seat.org/showthread.php?t=49030
ETA the bullet with the "*". Just heard about that one a couple of weeks ago and I wanted to have all of these in one place.