Originally Posted by Autodidactic player
That's the plan but as with most of these rackets the idea is better than the execution. The key fits in the butt cap and you turn it to add or subtract tension from the six center main strings. Since most of the control, power and feel on shots comes from the main strings, as opposed to the crosses, the thought was that you could add a bit of tension to the center mains for added control if shots were flying on you or take away some tension for added power and depth if that's what you needed. In theory this makes some sense. In practice - not so much!
Like the MacGregor Bergelin LongString in post # 164, after a couple of adjustments, you tend to wind up with strings of varying, unpredictable, tension and a loss of both power and control.
That's my Mcgregor below . Sadly The tightening tool is missing and even more sad is that there's a broken string and no way to restring .