I agree with not using the coffee can and dumping the hot coals on a full basket of unlit. I can't say that's what is causing the extra smoke, but have experience doing minion method with uds, and other cookers. Dropping coals on top of a full pile will get you a better overall burn.
Modded Brinkmann Gourmet. Basic UDS. Rescued 22.5" OTS. SJS Mini-WSM. Stubbs. B&B Oak Lump.
Cannondale 2009 F8 (for burning off all the great BBQ)