Both, depending on the nature of the messages and their frequency (I would sometimes send him a cluster within 2-3 days). When there were many and especially long ones, he often did not respond. When he did, the replies were simple, brief and to the point. All amazingly professional. I really like his communication style.

We would often address some of my emails in session when I wanted or sometimes he brought up what he found particularly interesting. He always knew in detail what were in the emails so he definitely read them and probably gave them quite a bit of thought on his own. He also mentioned a few times that he liked reading my emails and often felt tempted to engage more but did not, for the reason I described earlier.