Maybe "real deal" is referring to assimilating and acclimating to a skill rather than just copying a skill for its effect. In other words, skill mastery.
Also, 本物 can just be translated as "true". Then it would be a matter of a skill being a "True Skill" or an "Imitation Skill". Imitation being interchangeable with words like fake, replica, mimic, mock, facsimile, or even "Ersatz", which sounds nice and fancy. Comparing them as "True Skill" and "Ersatz Skill" fits well.
For those unaware, ersatz means something that has the appearance of something else but the actual contents explicitly being inferior.