1950snottypine:
The reason why the knots in knotty pine will bleed through a latex primer is because the knots have a lot of tannin in them, and tannin is soluble in water. Tannin is brown in colour, and so most woods that are yellowish or reddish in colour (like cedar, Southern Yellow Pine, Red Oak, Redwood, etc.) will have lots of tannin in them. Priming these woods with a latex primer is likely to result in the tanning discolouring the primer. Typically, people call that "bleeding through", but what's actually happening is that the tannin from the wood is dissolving in the water of the primer.
A shellac based primer like BIN will prevent tannin from discolouring the primer (cuz tannin doesn't dissolve in alcohol), but if you still see the knots after applying the shellac based primer just cuz of insufficient hide, then use a high hiding alkyd primer to hide the darker knots.
The hide you get will depend heavily on the colour and gloss level of the paint you choose. If you have a high hiding paint, you don't need to use a high hiding primer.