Yep,
Loading a boat on the trailer is different for each boat, trailer, ramp, and more. Some boats, including Pontoons and Tri-toons, will sit differently in the water. The way they float and or are influenced by even small gusts of wind can frustrate even veterans of boating while trying to retrieve the boats back onto the trailer, seen it many times. Then there's the trailers themselves. Different types of guides work in various ways, with lots of variables. The primary issue for many boaters, especially newer boaters is the angle of the ramp. Here in lake Havasu AZ, we have about 6-8 different ramps with various angles. Some are way steep and some are fairly shallow angled.
To me, a shallower angled ramp is better for retrieval but not so good for launching. A shallower angled ramp allows for more of the boat to settle into the bunks earlier in the retreival process but not so much that the boat stops in its tracks, so to speak. You still have enough floatation to add a little bit of power to nudge the boat further into its home on the trailer because of the remaining ability of floatation. A steeper ramp causes the boat to hit harder into the bunks with just the front end but the back is still possibly 18" to 2' away from their seats. And due to that situation, there's not enough bunks capturing the straight on angle of the boat and hold it and if there's ANY side influence, like any gusts of wind or even smaller wakes from other boats nearby that are either launching or retrieving, your boat will be influenced by them and drift off its intended path.
There's a few styles of trailer boat guides out there. What I call the "Goal posts" (like the ones in foot ball fields) are preferred by lots of folks. They work but like many when it comes to pontoons and Tri-toons, they are limited in performance. Then there's center toon guides. And there's a few forms of those. Some are full length and will start to guide a pontoon or tri-toon almost immediately and keep it as centered as possible all the way onto the trailer. And that's a good thing. Again, the angle of the ramp, your speed, any outside influences, how your particular boat sits in the water vs how deep your trailer is and more will all make a difference in just how easily your boat glides back onto its trailer. And of course, LOTS of practice.
Scott
P.S. By the way, if you want to get ideas on what NOT to do or what TO DO in proper loading of many styles of boats, just go onto Youtube and look up Lake Havasu Ramps or any other boat ramp scenario. Lots of those videos are a crackup watching folks try and re-trailer their boats.