1 - A soft approach
No matter the starting level of the participants. By level, I mean both the manual ability to handle bricks, as well as the desire (or a priori) to manipulate these bricks to find answers to problems. Once the learning phase is over, each participant gradually understands the interest and strength of the method.
2 - Touch as a fuel for thought
I am a big consumer of Post-it, the agilist's preferred tool to help people transcribe and organize their ideas. The advantage of Lego bricks is the addition of a third dimension. Thanks to it, hands are no longer just a means of relaying ideas (writing ideas on paper), but they become a powerful engine of creativity (building ideas). This new dimension provides more comfort to "get out of the box".
3 - A constant focus
During a classical workshop, participants may take their smartphones out of their pockets to check their messages. As a facilitator, I don't mind inviting them to put their smartphones back in their pockets. However, the strength of an LSP workshop is the implementation of short work sequences (challenge - build - share - reflect) that require almost constant attention. If at first some people are tempted to take their devices out, very quickly the rhythm, interest and constant attention on the "real" subject of the workshop make these devices quickly forgotten.