I came across videos of Road to Gehenna speedruns while looking for standard solutions.

I was impressed so thought I try and learn some of the moves.

I can do item jumps over gates and the jammer glitch to take a solo jammer through a gate. But neither reliably yet. Only once have a gained , what I would call, big air from an item jump but I guess practice will help.

What I can not work out is the cube jumps where the cube is placed to the side of an open gate and then when jumped on the cube and player take off on a huge jump.

(like here at 1:22 )

I've searched the web, this forum and watched a quite a few speedruns and tutorials but can't seem to find an explanation of how this is achieved ?

That is my main question but also if anyone knows of any videos which have in depth explanation / discussion of the various glitches and tricks I'd appreciate it if you could post links.

For instance the Jammer glitch. Sometimes I do it first time. Sometimes I cannot do it after about 40 attempts. (on the same gate as I've succeeded with previously) .I'm just copying what I've seen in videos but not 100% sure what the criteria for success is.

Cheers