Conference presentations are difficult work: take a big, messy concept or idea and distill it down to fit into some arbitrary time constraint pre-determined by the conference leaders. Credibility wanes when positioning that idea and the forced-simplification that follows. If the presenter is honest he or she will admit to their constraints and briefly cover what they can’t cover.
If the presenter is employing the marketing playbook, they may not communicate the complexity or subtlety being lost in the talk. They will hit message points without acquiescing to the limitations of their model. The audience should always go back and ask what they were’t able to include because incompleteness is as much the fault of the passive listener as it is the active over simplifier. Don’t be afraid to spend time with presenters on the show floor and pursue the details the time constraints strained from the presentation.
If you want to get the most out of a conference, challenge the speakers. Challenge the people manning the booths. Actively pursue the knowledge you seek. On good days you will be delivered incredible insights, on bad days, you may simply learn that the presenter doesn’t have the depth you seek, and that knowledge is valuable in itself.