I never done the pocket thing, but these two snips from my cookin' site confirm that I think an injection late in the cook is worth trying out. I mentioned it just the other day in the "When Do you Inject?" thread.
(Brisket Page) - An injection technique that I picked up from fishlessman on the Big Green Egg Forum, calls for skipping an intital injection when the meat is raw, and shooting it toward the end of the plateau or before the rest. The meat takes the juice easier than when raw, and it adds a moisture and flavor bump at just the right time.
(Injection Page) TIP - I have gotten a couple of suggestions for using an injection in the later stages of a pork butt cook. This would be done during the plateau or right before foiling and holding. I think this is a very good idea, especially on pork as I often use a sop after pulling anyway.
KCBS - CBJ
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