There are those that follow the school of thought that you should borrow to the max every year until 2042. My aunt and uncle follow this borrowing school of thought.
I, myself, don't feel comfortable doing this all the time but I understand the reasoning behind this school of thought. It's always nice to know that I have plenty of points in my "kitty" for all my future plans, but I have no problem with borrowing either.
Some background: My aunt is a fellow DVCer. She and her DH have 8, yes 8, children. They bought over 6oo points way back when during the very first year of
DVC when park passes were included - when they only had 3 kids.

I think they mentioned that they actually paid presale prices?
My uncle is an extremely busy bank financier. My aunt is an avid traveler who home schools her kids. She always off some where to an "educational" trip. He purchased DVC for her so that she would have a place she could feel comfortable taking the kids WITHOUT him. He only goes with them maybe once a year or every other year.
This is how he explained to me why always borrowing is a good thing:
1 - My aunt is extremely busy with all the kids. There's always the potential for banking deadlines to pass or points to expire. Two less things for her to worry about when they are in a borrowed state.
2 - Financially speaking, it's a much better value to be borrowed to the max. You prepay for the accommodation. You pay maintenance for the cuurent year's points or accommodations. Each night of accommodation is worth $$ - as rack rate or as a calculation of the price per price and the annual maintenance. Regardless, when you bank points, you are essentially "lending" the value of those points back to DVC interest free. Whereas, when you borrow points, DVC is "lending" you the value of the points earlier interest free. You are not paying any more or less money at any different time. But you are reaping the benefits of the value of the accommodations earlier. Ahhhh.... the working mind of a banker...
3 - Who knows what will happen the last year of the DVC contract. Will they have enough units at the times people want to go in the last year or two? (THEORY - They may suspend banking the last few years to allievate the "rush.") Will there be the potential of expiring points

if the dates you can go aren't available? By borrowing until the very end, you'll be taking your points earlier out of that "glut" of points that HAVE to be used the last year or lost.
4 - Borrowing was a REALLY good idea the last year that the free passes were availalbe because they provided the passes even on stays on borrowed points.
Well, these are some of the reasons why some people believe that borrowing to the max is not a bad thing and is actually a smart thing to do. My uncle thought that the most important reason was the financial reason. Time vailue of money and all that. O'kay...
Bottomline: Bank, borrow, do what you feel comfortable doing. But it's always nice to realize the pitfalls and advantages of each choice. So, thanks for the warning.