Marinades - Help

This is just off the top of my head and I'm sure no MFP Guru. 200-300 calories (per serving, right) sure seems like a lot to be added by a marinade. Oil, after all, is only 120 cal per Tbsp and I don't know how you'd get more than 1 1/2 tbsp to stick to a chicken leg. If it is an oil and vinegar based marinade you could guess 1/2 a tsp or so. Or you could weigh the chicken leg before and after marinating. Or if its the kind of deal where there's going to be a lot left over in the marinating dish, weigh the marinade before and after . I marinate catfish in buttermilk but I don't figure enough butter milk stuck to the fish to even warrant counting. I do count the flour and cornmeal and I suppose if the food police were gonna audit me I'd add 1 or 2 calories for the 1/2 tsp of buttermilk.
Reread your post and if the question is how much is on the chicken when you put it on the grill compared to when you take it off, I'd say all or at least most.

I often think this with marinades and sauces but log it as the full amount, if anything it means I'm over estimating my food which is what I would rather.