I'd be cautious of anything endorsed by Rob Dahm. In spite of the buckets of money spent on his builds, he is sloppy and ignores safety. It is going to bite him one day.
I third this about Rob. He seems like a well meaning, okay guy. His content can be entertaining, but he clearly takes short cuts and makes questionable decisions. There's arguably more to learn from his mistakes than anything. He's also a youtuber, which should be an automatic strike on one's credibility.
MPbdy is right, though. It will change the point where the IC occurs. It does less to solve the issue than the Ronin bumpsteer correction kit, as that allows you to adjust the angle of tie rod and thus the intersection of the IC and the virtual line created by that tie rod end.
Changing the effective height of the upright particularly by a small amount should only minimally change the camber curve if at all IIRC. Camber gain/loss is most affected by the difference in length between the control arms. Which isn't to say that upright height plays no role, or chassis side mount separation no role in camber change, they do. It is just the case that the adjustments have to be much larger to cause the same amount of change you would get by changing the ratio between the control arms. That's my memory of things from playing with suspension geometry calculators, anyway.
Brief aside: regarding lowering, FD drop spindles would be really cool.
Finally, none of this is intended to repudiate the idea of correcting the role center on a lowered car. That makes sense, IMO and would be the reason to get this kit. Provided you went low enough to merit it.
