Email spam or directly spamming your hoplink has a high likelihood of banning. However spamming blogs which then in turn advertise clickbank products has a lower likelihood of banning. Clickbank is actually pretty loose when it comes to "aggressive promotion" - I think they just have so much volume and so many webmasters that it's easy to get caught in the mass.
However, ALL programs can and will ban for spam if you get too many complaints, so it's just something to figure into your strategy. You spam at your own risk.
Stay away from Peerfly like the plague if you are doing any kind of spam, they are zero tolerance assholes.