OK, so why did BlackBerry settle rather than fight?

I know why. Research In Motion execs were able to bite the bullet on stubborn pride, and agree to a settlement based on the accurate assumption that it would be more expensive NOT to settle than TO settle.

Let me tackle this by detailing what financial types call ROI, or return on an investment.

As a consequence of all this uncertainty, RIM today cut its forecast for net subscriber additions in the current quarter that ends this weekend to 620,000 to 630,000 from its previous forecast of 700,000 to 750,000.

Averaging those two numbers means 100,000 fewer subscribers than hoped. Multiply that by four fiscal quarters. Given carrier revenue splits, that would equal around $35 million in losses per year.

Add to that the fact that 100,000 fewer subscribers would mean 100,000 or so fewer BlackBerry devices sold for the quarter. Multiplying by 100,000 a quarter, that would mean 400,000 for the year. At, say $399 a clip,that's another $150 million or so.

That four-quarter arithmetic is especially relevant to BlackBerry's enterprise business- where BlackBerry server and equipment purchases are often negotiated many months in advance. Thus, the continuing effects of uncertainty would be ongoing.

So far we are approaching $200 million, but the main number-crunch is still to come.

The real issues are stock price and enterprise contracts.

Dennis Kavelman, RIM's chief financial officer, told CNET today that RIM was feeling the effects of enterprise customers waiting for resolution in the case before expanding their current BlackBerry usage or upgrading to new hardware and software.

That's where the high-dollar ROI really starts to apply.

Then let us look at the stock price. In after-hours trading, RIM stock gained 19 percent to $85.20 a share.

Before the hike, RIM had a $13.32 billion market cap.

Even leaving out the effect of uncertainty on lost revenue, simple math shows that a $612.5 million hole would require only a 4.6% stock price hike to produce a market cap gain that would exceed the money paid to NTP.

I haven't even mentioned revenue from BlackBerry Connect email sales to carriers, as well as how much RIM must be paying their pricey, mostly outside legal teams.

Now, it's over and BlackBerry can get back to business.