My specialty is cutting through the bullshit. To test which break is best, I hit 200 breaks on the same table (GC3), 100 head ball breaks and 100 second ball breaks (alternating 25 each), and wrote down how many balls were made in what pockets and how many balls ended up in what parts of the table. The difference in balls made on the break and how far the balls spread was minimal. The most interesting fact was that I only made a ball on the break about 1 out of three times either way and never made an 8 ball either way.
So, frankly, I don't think the second ball break is worth the added complications, but if you feel you have to do it, hit it center ball. Low is OK, but sidespin of any kind is just asking for trouble in exchange for a mythical reward.
And whoever told you to split two balls on the break hates his money.
pj
chgo