A few recipes I have tried calls for some liquid, typically a ladle of stock or broth, to be added to the baking tray before placing into the oven to finish the cooking process. (To assist in cooking the protein, not crisping the skin) For example, a pan roasted chicken thigh is pan fried quickly to colour the skin before placing into the oven, skin side up (bottom and inside basically raw)with a ladle of stock. 15 minutes later, the chicken is cooked nicely but the skin is not crispy. I have my oven set to 200 degrees celsius fan assisted. I suspect its all the water vapour inside the oven preventing the skin from becoming crispy as when I open the oven door, a large cloud of steam is released. What could I do to fix this? Another example would be when roasting a belly pork with crackling. The belly sits on a rack above a tray of water. When the pork cooks the juices collect into the water below in order to make a gravy afterwards, but the skin isn't always as crisp as I hoped. 
I'd agree with the other answers - adding liquid won't really aid crisping of the skin, if you are using the pan fry and then roast/braise technique that you describe (which I do like, and often use) I'd make sure that the skin is really crispy and browned in the initial pan fry (that's basically the point of that first step) - it might take up to ten minutes, but I generally find if the skin is properly cooked then, it doesn't get soggy in the second step. The great thing about the technique is that its easily adjustable to basically any flavour combos, the braise is more for flavour/gravy rather than cooking - as Kenji covers here - note he also mentions early on the importance of thorough cooking of the skin and to keep the liquid level low enough to make sure you avoid this exact issue. If you don't want the sauce/gravy with the chicken then cooking dry in the oven is the way to go. The only possible reason I can think that someone might suggest adding the liquid could aid crisping of the skin is that it essentially means you can roast the skin & top of the thigh, whilst the meat underneath is braised. The braising liquid insulates the flesh and allows that to cook more gently whilst the skin at the top is subjected to the higher, drier (of not fully dry) roasting heat - but even with this guess, I wouldn't recommend it as a technique if the goal is purely crispy skin (if that's your only goal, then dry roasting is better). 