mentioned some guidelines he felt should be observed
Sorry - what were those again?
If the intake duration exceeds 240°, the later cylinder will cause a minor leak as its valve begins to open, but since this is BTDC vacuum is minimal, and no actual flow will occur until the piston moves down ATDC a bit and the lift reach perhaps .020". The earlier cylinder is already coming up to compression in any case.
In addition, #1 & 6 do not have this problem, since their complementary cylinders (#2 & 5) are 480° later and cannot interfere.
I believe this is what I was thinking about that you mentioned.
