Situation A) User has an assload of mods (3 damage meters, a threat meter, etc...) that all send tons of information and he decides "Hey, I'm going to install BigWigs since all the cool kids are doing it". To make this even more complicated lets say hes an dumb raid leader, and the main tank at that. Raid time comes and zomg, he keeps getting disconnected during boss-fights. He decideds "well, the only thing I recently changed is BigWigs, so this mod must suck!". He was kicked becuase BigWigs was sending the 'straw that broke the camel's back' so to speak. He tells his guild to not use BW becuase "it sucks".
Situation B) Same stupid user again has an assload of mods, this time they all use CTL. He decides "Hey, I'm going to install BigWigs since all the cool kids are doing it". Raid time comes, and oh noes! BigWigs messages seem delayed. He blames it on server lag and decides to deal with it.
Honestly, people who aren't bogging down their system with a ton of stuff are going to send the messeages immediatly regaurdless, becuase they have the space to send it. Also this ignorent-user is still going to recieve those sync messeages, on time, from the smart user. The ONLY things it's going to cause issue with is things like NefCount that are counting most/all users sending things instantly and acurately.
Given the two hypotetical situations, I'd rather see situation B.