That place will get the best of us. We launched there all the time when we lived in LHC. Slow and careful even then it can be frustrating.
Your trailer goes 6' under real quick. Then, in only a couple feet of moving forward, WHAM, your trailer is coming out of the water and your boat is sitting on the trailer cockeyed.
That is why Bob McCulloch used it for his secret test facilty for his outboards. You could back a boat in just a few feet and have it in 6' of water. Also.... back in those days old Mr Evinrude could'nt find him to see what he was up to in R&D as they battled it out for the Outboard Market. We know who won