I have an older (1960s), original FS tilt trailer.
There is a squarish U-bracket about 6 inches behind where the trailer tongue forks out into the two side supports on the frame. Along with a bolt about 3 inches forward of it, the bracket seems designed to control the tilt of the trailer. 
On my trailer, this bracket is bent flat. I need to decide if it is worth repairing (and given the condition of the bracket, anticipate I might need to have a replacement fabricated).
1) Do users of tilt trailers find this function especially useful or do you typically have it in the locked position? 
2) Does it aid primarily in launch, retrieval or both? 
(This question is important to me since, while I have no launch troubles, I often have some trouble getting the boat well centered over the rollers upon retrieval.)