I mainly tow gooseneck equipment trailers. But between them and semis , I could count the number of times I've been close to 90° on my hands (and the trailers would be empty when doing this). And never close with a 5er.
With the rounded fronts and extended pinboxes, most trailers (rv 5th wheels) are able to be towed without a slider. That and the fact I dislike the strain on axles, tires, and suspention on a loaded trailer when turning even close to 70-80°, ill just add a couple more points to my turns!
To each thier own!
MillerTime- Future Sabre Handler!!