When connected with each other, the human or Nebulan and the Transformer essentially share a single mind and can work together seamlessly, but when separated from each other, both retain their individual minds and bodies. This allows for greater cooperation, and with twice the experience, a better understanding of possible combat or other dangerous situations. The binary-bonding process does not damage the body of either party, and both parties are able to carry on with their normal lives, but it does generate a permanent, irreversible bond between their minds. However, the Headmaster component can find themselves with increased strength.
The process does have a few weaknesses. Some partnerships on both sides suffer from issues partners have with one another. For example, Vorath is a scientist while his Decepticon partner, Mindwipe is a believer in the supernatural, leading the two to bicker over conflicting ideologies. Also, headless Transformers can be stuck in vehicle mode when the Headmaster component is separated.
— Wikipedia on Headmaster (Transformers)
2012.04.10 Tuesday ACHK