Coaches can use 'training blocks' to write a wide variety of content and ask their clients to provide comments for review just as if a client were writing performance notes for a part of a day.
A training block can be given any title. Bear in mind it's useful to use consistent titles as this is a search option in 'workout history'.
The free text content does not necessarily have to be a workout description. It might list feedback a coach would like to hear from their clients.
Clients input any kind of feedback by writing it as a comment to that block section / training part, just as they would if writing performance notes about how that part of day's training went for them.
Coaches can review and reply to anything written about a part / block in the day exactly as if reviewing and replying to clients' performance notes.
Any block section(s), day(s) and week(s) in any program can be saved as a template to be inserted elsewhere without the need for rewriting the same material.