See title. Frankly, this is the only change I personally believe absolutely needs to be implemented for world events. I expect the high gem cost of the last event to not be adjusted or not to be adjusted significantly, but that’s a separate topic.
If it is not revealed explicitly how to optimize scoring in these events, it becomes advantageous to not use one’s own sigils until knowledge of how to do so is obtained by other players. Because these are guild events, this incentivizes the entire guild to not play until later in the week. This is especially important because even minor scoring optimization will save hundreds if not thousands of gems over the entire guild, for example if doing so means the average guild member need only buy Tier 6 versus needing to buy Tier 7.