I have had some close calls when fishing my way under bridges on small creeks, you gotta be aware of your clearances. Over the years I have had to have three repairs made.
1. Orvis Far & Fine 1994; first time I ever put rod in the bed of truck assembled and drove to a new location, 1.5" broke off tip.
2. 1996 I placed my 9' 5 wt PM 10 in the back seat of Bronco (disassembled but not in tube) when I stopped to check out creek my Pointer bailed from the cargo area into the back seat, tip broke in half.
Some guys never learn, this was the first time I had ever done this also, this rod was very expensive but for some reason I thought I didn't need to tube it to move a few miles.
3. By 1998 I literally cast the tip of my bamboo flea rod to death. It splintered about 6" up the tip section while I was fishing Slate Run. This was the only case where I was not at fault through carelessness and I had an extra tip so the show went on.
Now the point; in every instance Orvis required that the entire rod be shipped back to Manchester so that new tips could be properly matched to the rod. It will be the same with a St. Croix I'm sure. The rods are specific when it comes to matching tips, mids etc. You can not just put any tip on a rod even if it is made by the same manufacturer and is of the same model. Sorry to hear that you have had a problem but this is how we learn to be careful with our fly rods.
In 1996 I bought a magnetic rod carrier (tower type) from Orvis. This gizmo allows you to lash a fully rigged rod to the hood and roof of a car or truck when you just want to move a few miles up or down a road along the river. I love this thing and have used it so often that I wore out a pair of clamps on it. Here at home I can don my waders and fully rig a rod complete with fly and then drive to a nearby creek. When I get there it is simply a matter of pull over, grab the rod, and go fishing. Same thing applies when you are done, I rather enjoy breaking down my rod and removing my waders at home as opposed to doing so along a public roadway.
Not sure that answered any questions, Mark did that but I was compelled to write all of this anyway.