The shot's probably not possible with clean, polished balls unless you get really, really lucky and chalk transfers from the tip to the cue ball and then happens to land on the contact point. I'm not sure if this is possible on a single stroke for this position, but I have done it once intentionally with the cue ball much closer to the object ball.
Joe Tucker has a video of a similar "impossible" bank that he makes 3 out of 4 tries. I heard he tried it later on clean equipment and couldn't come close. I suspect that the legendary road players who are said to have shot such super spin shots as propositions either relied on rarely cleaned equipment or "happened" to palm the object ball with the same hand they chalked with.
Anyway, I think of the cut off the spot as a "one hour shot" in that I'd bet on making it in an hour.
As for fundamentals, when playing pool I stand like a pool player, which is to say like Irving Crane and Willie Mosconi. I'm probably too old to change. On the other hand, when playing snooker, I stand a lot more like a snooker player, back permitting.