cant' answer any color questions,
but spotting is labeled with an S. you need to have ss to be spotted. the black gene is labled with an E, with ee being red. so yes, since these are two genes, you can have a homozygous black animal with spotting. it would look like this. ssEE
i'm thinking heatwave is SsEe as he throws spotted cattle and red cattle. so... getting a homosolid homoblack polled THF calf with his phenotype and is able to pass it on is going to be pretty rare. probably why clones are used so heavily for steers now. i'm actually kind of shocked there aren't more red heat waves out there.
most people want SSEE. there is a test for homo black, but not one for spotting. those solid homoblack direct descendents of magic, in my book, are reasonably valuable. i know what i would cross them with in a heartbeat if i had some. supposedly, you can linebreed them and you won't have a wreck. a couple of people have lots of them, probably the most numersous, are the reflector lines. when you double up smithbuilt in the same field, supposedly you lose at least one frame score. the trick with these is obviously to get that lower quarter with that nice hip in a homosolidblackpolled package.