It is true that the actual TLAG depends on quite a number of things (i. e. type of food/food particle size, gender, body size, position, movements, deseases,...). But no matter what you assume, the TLAG is limited as the stomach will start to pass on the chyme eventually.
Yep, but that's what we got. I think if somebody would conduct a study to find if a TLAG of well over 180+ minutes is reasonable it would be of great help to future forensic analysis. The articles I have read so far all show that the TLAG of a healthy person is somewhere between 30 and 90 minutes under laboratory conditions. So if we double that to 180 it is already a big stretch but still would put the TOD to 21:30 tops.
Of course this does not give a "certain" TOD, but it's certain to a reasonable degree that a TOD around 21:00 - 21:30 is more likely than at any later time. And this is what I think will be Hellmann's reasoning in the report.
Forensics indeed use the gastric emptying data to determine the TOD if certain information is available (I think they need the time of the last meal, but I'm not sure). However, they usually rely on the actual emptying after the TLAG and not the TLAG itself. Also I'd like to know where you got this 12 hour error from. In 12 hours two meals are passed on completely, so how could they err by that much?
-
Osterwelle
Machivelli is sadly ignorant of the underlying science and physiological factors underpinning the ToD argument. As many others have already pointed out in response, in this particular instance we are fortunate enough to have a near-unique set of factors which enable us to confidently place practical limits on ToD. These factors are:
1) the known start time of the meal (around 6.15-6.30pm start to the meal (Pizza course), with a dessert at perhaps around 7.45-8.00pm);
2) the known composition and size of the meal (pizza then apple crumble, small to moderate volume);
3) the known fact that the victim was still alive some 150 minutes after the start of the meal, at 9pm;
4) the known fact that T(lag) - which is ALWAYS measured from the start of the meal for reasons which should be obvious to anyone who stops to think about it for more than a minute - is rarely longer than 150 minutes, is almost never longer than 180 minutes, and is relatively statistically vanishingly improbable to be longer than 240 minutes;
5) the known fact that recognisable elements of the pizza were found in Meredith's stomach at autopsy;
6) the known fact that the 500ml contents of the stomach at autopsy are entirely consistent with the volume of food likely to have been consumed by the victim at her final meal;
7) the known fact that there was no food (chyme) matter in the victim's duodenum at autopsy, or in any of the rest of her c. 5-metre small intestine apart from at the very end;
8) the clear ability therefore to deduce that the entire meal (pizza + apple crumble) was still entirely within the victim's stomach when she died;
When all these factors are assessed by anyone with a rational and scientific mind, it becomes easy to deduce, with a very high degree of statistical probability, that the victim was killed between 9pm and 10pm, and that within that range the strong likelihood is that death occurred before 9.30pm.
Machivelli will see that Hellmann will likely make such a point in his motivations report. I realise that he won't accept the argument (just as advocates of Homeopathy's pharmacological benefits are blind to the science which utterly refutes their "argument"), but perhaps he ought to stop to wonder why even the prosecutors conceded a pre-10pm ToD in the appeal trial.......
Maybe you didn't notice, but the innocents are no longer in precautionary detention, they are absolved and free, enjoying life ( something all the bitter bunnies and kittens should try ). 
