Split Lobe Separation Angles?

Full disclosure - I think I've actually built 3-4 hydraulic roller engines out of probably 60+ over the years. Solid rollers are preferred by me and I bush every block for them. But even those rare for my customer base. I've never seen, nor think I've ever heard about an issue with uncovering the tops of the lifter bores on a big block. I have heard about some smaller base circle cams leaking out the bottom - the roller supports on some lifters can uncover the oil passage - but that's why the deep bodied lifters exist. When it comes to hydraulic conversion rollers I have gone with Howards. At the time others' weren't available.
Small blocks cast and machined after the mid 70s, oiling problems are fairly common and I'm fairly sure Mike among others have lifters for that issue.