Hey i need some tips for a PJ in OOB space at the refinery (R-01). I can go on the roof no problem but going back inbounds is the problem. Mabye its the hight but i tried many times and it didnt work.

The first part of the skip (where you do three PJ's in a row) does not require that much of a height to get on to - even with a huge offset to the correct timing, you'd still get it anyway. The second part of the skip however, requires near-ideal jump, meaning that the offset has to be minimal. The correct timing would be a little gap between the "gasps" that Raiden does between the two polearm attacks (you can hear this if you turn off music and sound effects), tap RM just as the first gasps nearly fades away, you'll probably be getting much better PJ's, and if you were to press RM early you can easily adjust to that.

Not only that, but you also have to cancel out of 3rd (if you've gotten a good one) or 4th (if you've gotten the timing slightly wrong) attack, 5th attack loses you height (unless you cancel it during a specific frames where you get a bit of height, refer to Lukami's guide). Plus, if you're doing a setup from the right corner (as opposed to the left, a bit more consistent one), there might be a bar going out of the roof that kills a lot of height during the initial polearm jump, so if you were doing the setup from the right corner, try the other one.

The skip, if done correctly with no mistakes, saves around 12 seconds in an hour run, failing the last jump costs ~4 seconds per try, and after two jumps you'll be losing time. The other strategy (that involves going the "vanilla" route and then doing PJ from inbounds or using an RP grenade, whatever you want) can give you more runs in a long term, giving you enough polearm practice in a run, until you can consistently manage the height you need to get past certain barriers.

I can't say for sure since I haven't actually seen you do it, but when I do it, I think my success rate has increased since I've been conscious of putting a little "pause" between rising after the RM and canceling with the light attack in the air.