You are welcome Peter and good job on your delicious Lamb Shanks.
It seems to me that for SV you might need to cut the hard vegetables smaller than you usually do when braising. Small dice (aka brunoise) vegetables will soften as the meat SV cooks and should completely cook during the reduction as long as the reduction lasts 8 to 10 minutes.
The key is to not overcook the vegetables to the point where they have become tasteless mush which often occurs in a long braise. When braising i usually discard the cooked vegetables that have given up their flavour and add fresh ones to the mixture for the last half hour or so. You might try doing that in the reduction stage to get the improved vegetable flavours you were looking for. Always taste as you go.
I don’t understand your culinary term, " . . . did not work out on the meat". If you mean, - infused with flavour, it usually doesn’t, Besides lamb has it’s own stronger flavour that may dominate the other ingredients. That’s why we use injectors, but that’s beyond the scope of this post.
Answer: I’ve given you my opinion on searing meat to be cooked in a mixture. I don’t find it worth the time and effort. You might, - hey it’s your food. Remember, one-inch cubes will require less cooking time. Meat’s meat, it won’t absorb much flavour beyond the surface no matter its size. That’s the reason why humans invented ketchup and other sauces.
To enhance vegetable and herb flavours we usually just add more to the menu item. Woody herbs can be added early. Soft herbs go in at the end to preserve their delicate flavour and aroma. It usually takes twice as much of an ingredient to make a discernible flavour impact in your recipe. That’s the way our sense of taste works, it’s geometric.
Cooking Hint: The cat usually finds it worthwhile to occasionally brown a half dozen cooking onions in a little bacon fat and use them as an ingredient when appropriate in a variety of items from on Pizza, in Stew, Quiche, even with Lamb Shanks. They are a significant time-save. They can be frozen in recipe-size parcels and they will keep for a couple of months if you don’t cook much. Remember to label and date everything to prevent freezer mysteries.
Bonus Hint: A mixture of those caramelized onions with an equal amount of chopped raw onions, an old west side of the lower Mississippi River trick, adds an interesting complexity to dishes like your Simmered Chuck Roast or Lamb Shanks. Add them mid-cook or later.
Happy cooking.