We're still not 100% certain if there's an 'Abolishment Party'. It could be a scare tactic or it could be real, but I think there's more to the details. The primary idea, when stripping away all the fluff, is that you've got a radical voter willing to vote a soft option. If there is a party that wants to maintain a tie, then knowing which option I'll vote for easily allows them to continue a tie and perhaps force an event. However, by not knowing which soft option I'll vote for, they have no way to plan anything.
If this is a Shadespiracy, then you still win by having a radical voter go soft. Orange could watch me to see how I vote, but that ruins the point of your bargain. You want soft pluralism to win. So, we need to add another element to the mix somehow to maintain the randomization of the soft option.