Showing unfinished work every week removes the reveal, and with it the argument the reveal reliably produces.
The presentation format teaches clients to hold their reactions for six weeks and then deliver them all at once, about work that is now too far along to change cheaply. Both sides know this and both sides keep doing it.
Show it before it is good
A weekly half hour, same time, with whatever exists. Sketches, a dead end, a question. The client sees the reasoning rather than the conclusion, and learns to comment on direction instead of finish.
The first two are uncomfortable. By the fourth nobody remembers presenting any other way.
Clients learn to save their reactions for the reveal, and then they arrive all at once.
Separate the question from the update
Open each review by naming what you need a decision on. Everything else is context. Without that, a half hour becomes a status meeting and the decision slides another week.
One decision per review is a reasonable rate. Three is optimistic.
Keep the record short
Three lines after each session: what was shown, what was decided, what is next. Circulated the same afternoon.
Six of those lines are a more useful project history than a deck, and they are what settles a disagreement in month four.