do the memories have any significance? if it's not going to hurt anything by having them there, than I'm not going to worry too much, I'm just a little worried that it could be a sign of something a little more serious that may attack later. Ness
This is my personal opinion on this matter and there will be others with different views.
The only memories that
I feel matter are the ones that involve a token and any memories that refenece an ID# such as a Sim's character ID# that has a direct memory shared with your Sim and that is not an invisible memory.
For instance, in Veronaville, Juliette Capp and Romeo Monty both have a memory each of Mercutio Monty catching Hermia Capp cheating, as well as a memory of Hermia Capp being caught cheating by Mercutio Monty. Both of these are invisible memories to Romeo and Juliette and in my opinion are not especially useful. If you look at both Mercutio and Hermia's memories, neither one of them have their own memories of cheating and being caught cheating.
It really is a matter of preference for you, especially if you are telling a story or reading through the memories of Sims to get specific information, such as for rebuilding or creating memories of other Sims. This can be quite useful. If your logic seems common sense to you, then I would go with your instincts. If you are doubtful or feel they may be useful later, than leave them for now. At some point you may want to purge the memories, but just keep in mind the memories that they may share with another Sim.
I hope this makes sense to you.