To be honest I stopped reading after the initial focus on writing vs having a chat with someone.
Maybe that works for some organisations but I'd much rather my team talk through a problem than engage in long protracted email threads.
It's almost always better to immortalize the context sharing in writing. Decisions can be bucketed into categories, and those categories are revisited over and over with different constraints each time. Being able to easily recall arguments on both sides is very valuable to the company, less so the individuals, but very much the company.
Personally, I try to have a conversation and then ask for it summarized in an email. Simply because walking through the office will leave me with 10 action items and I am not going to keep this in my mind.