Hello all. Just wondering if I could get some confirmation surrounding the Echo. I have a fairly good hold on Eorzean lore in general, but not able to find solid answers for these:

a) Do we have a list of people who possess the Echo aside from ourselves and Minfilia? Are Cid and Alphinaud included?

b) Are we able to enter someone's memory at will? Consciously, by ourselves.

Thanks.