BBQ Tests - how long at temperature to produce pullable BBQ?

I wanted to determine how long it would take, at a given internal meat temperature, to produce pullable BBQ.  So armed with a thermocouple and a Sous Vide machine, I took some tests.  I was hoping to insert the spreadsheet that has the data, but so far, I haven't been able to find a way to do that...still evolving.

Here's a summary of the data:

The purpose of the test was to allow me to obtain some data that would allow me to select a desired time (just like my need for 6 hours today!), and then determine what the temperature should be held at for the meat's internal temperature.  The data was obtained from a thermocouple inserted into the middle of a controlled cross-section of pork shoulder (boneless).  It was then cooked in a Souse Vide machine (in a bag to keep out the water), at a controlled temperature (+/- 2 degrees) until the meat (in my subjective judgement) was pullable.

The test was to determine the length of time necessary to produce pullable meat if  the internal temperature of the meat was held at a controlled constant temperature.  The time to cook at temperature is started when the meat reaches the stated test temperature.  It does not include the time to bring the meat up to that controlled temperature. That's very important to understand.  Since bigger pieces of meat require longer to come up to temperature, that time would vary depending on the size and shape of your meat.  However, once it's up to the controlled temperature, the question was - how long does it need to remain at this temperature before it becomes pullable (and that's subjective based on what I consider pullable).

So here is the summary of the data.  

Controlled Temperature                Time at Temperature to become pullable

145 dF                                        41 hours

155 dF                                        31 hours

165 dF                                        14.5 hours

175 dF                                        bad data - temperature probe pulled out

185 dF                                        5.25 hours

195 dF                                        2 hours

I did a scatter-plot of the times, and they are predictable.