I hate this for you. A slant, and I own four, is literally the only razor of the 15 or so DE razors I have that gives me consistently smooth, irritation free shaves. Hell, I’m still struggling with the Mergress I bought a month ago.
For your slant, study the razor a bit and you will see the ”teeth” on the cap and the “teeth” on the guard make a nearly flat surface. Place the head of the razor, without a blade, against your palm and rock it back and forth and I think you will see what I’m talking about. You want this flat surface against your face. That is to say, dont “ride the cap” or “ride the guard” as some people describe. With a slant you ride both.
Also, be absolutely sure the blade is aligned. this is kind of hard to judge but if you hold the razor vertically and look down on the cap everything should be perfectly symmetrical from one side of the razor to the other. The blade should be parallel to the edges of the cap as well as the guard. With my slants I almost always have to loosen the handle a bit and slide the blade into the right position a bit.
Finally, my real breakthrough on a slant happened when I went to a Feather blade. A Derby was ok but a Feather was the bomb.
Good luck.
Really appreciated your advice here. I tried the slant again today and after 3 passes got a near bbs shave. I realised reading your tips that riding the cap was wrong for this razor and tried riding the bar more. Plus the blade was indeed misaligned; quite badly I might add. The culmination of correcting these factors produced a decent shave.
More work is to be done in getting the right technique with this razor, but I wanted to thank you for your helpful input!