I've been doing this long enough to know that "proprietary model" and "double" rarely show up in the same sentence for the reader's benefit. But Netflix is genuinely the most interesting large-cap conversation happening right now, so it deserves a fair hearing. 247 Wall St reports the stock has shed a third of its value over the past year, and Fool.com's tracking puts the decline from the high even steeper, at about 42 percent. Either way, a quantitative model is now flashing a signal that has traders paying attention again.

So start with what we actually know. A decline of that size for a company of Netflix's quality is not a small thing. The market is repricing something: growth expectations, competition, advertising revenue timing, take your pick. When a stock falls that far, the price no longer needs heroic assumptions to work out. And that is when the math gets interesting.

Here's the simple version I'd run before trusting any proprietary model. This is pure arithmetic, an illustration and not a forecast from me or anyone else: if a business compounds its earnings at 15 percent a year, you get a double in roughly five years from earnings growth alone, before any expansion of the multiple the market is willing to pay. After a drawdown of a third or more, the odds that you're paying peak prices for that growth go down considerably. None of this requires a miracle. It requires the business to keep doing what it's been doing, and that assumption is doing all the heavy lifting.

The risk, of course, is the mirror image. Streaming was supposed to be a winner-take-all business, and it turned into a spending contest where everyone fights over the same subscribers with the same content budgets. Netflix won that war, mostly, but winning a war and printing money are different activities. Ad tier monetization, password-sharing crackdown gains, and live events all have to keep delivering. The market has already shown it will punish the stock hard the moment any of those numbers disappoint.

What I'd caution against is the framing of the question itself. "Could Netflix double?" is a trader's question. The better question is whether Netflix at today's price offers a return that compensates you for the risk of owning a single company whose fortunes ride on subscriber behavior and content spending cycles. Sometimes the answer is yes. But if you'd lose sleep over another big leg down, which is entirely possible and has happened before, the position is too big regardless of what any model says.

Netflix has had brutal drawdowns before. Deep ones. People who owned it through the whole ride still came out fine, and people who bought the dip discovered they'd bought halfway down. Both stories are true. Concentrated bets on great companies are like that: the outcomes can be wonderful and the road is brutal.

My usual answer stands. A total-market index fund already owns Netflix at whatever weight the market thinks it deserves, and it owns the other several hundred companies that might double instead. If you want to add a personal position on top of that, size it so being wrong doesn't change your life. Patience and consistency beat a model's signal almost every time.

Not financial advice, just the perspective of someone who's watched "the numbers are getting interesting" play out both ways for four decades.