Nice job on the bird, you done did good.
I have used Royal Oak briquettes, I assume you mean Royal Oak by RO, and they do kick off a fair amount of ash, they are nothing like lump charcoal. They are similar to Kingsford and some others in terms of ash. Just a function of using briquettes. On the other hand, they are a good product for using in a a UDS.
I'm feeling bearish, and I'm packing a Wusthof Grand Brisket slicer from MABA
"perhaps...but then again...maybe not..."