Some fluctuation is normal. I usually catch my temp on the way up, and tweak the adjustments from there. Try not to make large adjustments. I prefer lump over KBB, because my UDS doesn't like the added ash. I also agree with lowering the intakes. Just my 2 cents worth.
SNPP w/ mods, Patio Master(30 years old), Kettle Grill, Copper Penny UDS, and Maverick 73 thermo.
Youth and enthusiasm are easily overcome by old age and treachery.