Are bidding systems geared toward "optimizing" contracts?
Bidding systems, particularly ones experts use against experts, are built around optimizing results overall, not contracts.

Half the time, the opponents have better hands than you do, and you are still trying to make their results as bad as possible.  Sometimes this is by sacrificing - getting to a contract that goes down but for which the opponents score less for setting you than they would for making their own contract.  Often, this is simply by disrupting the bidding enough that the opponents cannot exchange enough information to decide on their best contract.

At the slam level, and even frequently for games, experts are frequently thinking about the entire probability distribution of what partner's hand could be, what opponents' hands could be, looking at their hand, and calculating if there is at least a 50% or 35% (depending on form of scoring and vulnerability) for the contract to make.  They are not counting points.