Hunted spike elk in UT many times (archery and rifle), quite a few different units. One thought to keep in mind: Approximate numbers, but roughly 5-10% of a heard is a spike. Or, 5-10 targets per 100 elk. Others are cows, branched bulls, or calves. That is mainly why success rate is really low, there aren't many targets. Coming from out of state (increased cost of tag, fuel, etc.), seems one might want to wait for an any bull unit tag, which increases targets to 20-40% of the heard (depending on unit). If you have hunted elk a bit, just think about the number of spikes you have seen. Handful relative to the overall heard, just makes it hard to find a target (on top of finding elk to begin with).