Welcome to the Cake Decorators Q&A
number of dowels
Are 9 dowels really necessary fin an 8 inch cake that is supporting a 6 inch cake? I can understand that amount used in the larger 10 inch base cake, but I would think that 5 or 7 would be plenty for the smaller ones.
Also is dowelling necessary for a tall cake (6 inches+) that is really just one tier, but that consists of 3 or 4 layers all the same size?
Paul prefers not to take any chances with cake support hence the 9 dowels method for each tier. He does say in one of the tutorials that some people use the dowels corresponding to the size of the tiers eg 10 dowels in a 10" cake, 8 for 8" cake and decreasing going up. I've seen tutorials where only 4 dowels are used! Paul's method makes sense to me, it takes care of any dowels which could for whatever reason fail.
In a tower dowelling helps to stabalise the structure enough to pervent any sideways movement.
I can say only from my own experience, other members may find differently and will hopefully comment their opinion. Hope this helps.