Sherlock Holmes is an unparalleled genius. Warlock Holmes is an idiot. A font of arcane power, certainly. But he's brilliantly dim. Frankly, he couldn't deduce his way out of a paper bag. The only thing he has really got going for him are the might of 1,000 demons and his stalwart companion.
Thankfully, Dr. Watson is always there to aid him through the treacherous shoals of Victorian propriety and save him from a gruesome death every now and again.