Dear Glai, If you are asking me, try searching the Vinyl Asylum for discussions of skating force. Some pretty knowledgeable guys used to post on these topics, altho of late (the last year or two) most threads are about trivia. Or, try Google.
AFAIK, the various tonearm alignment geomtrys (Stevenson, Lofgren, Baerwald, etc), are about where to place the two possible null points along the path of the stylus from outer to inner groove, and to minimize average tracking error in between those two null points. (Where "null points" means points where there is zero tracking error. You can only have two of them in an arc traversed by a pivoted tonearm.) The Stevenson geometry happens to place the innermost null point closer to the spindle than any other standard geometry, which is why Stevenson is not commonly used any longer, or so I was led to believe; most tonearm designers favor placing the null points toward the outer groove for maximum fidelity. The various geometrys will affect skating force insofar as the optimum tonearm offset angle will be different for each geometry. I'd have to think more about that, though.
AFAIK, the various tonearm alignment geomtrys (Stevenson, Lofgren, Baerwald, etc), are about where to place the two possible null points along the path of the stylus from outer to inner groove, and to minimize average tracking error in between those two null points. (Where "null points" means points where there is zero tracking error. You can only have two of them in an arc traversed by a pivoted tonearm.) The Stevenson geometry happens to place the innermost null point closer to the spindle than any other standard geometry, which is why Stevenson is not commonly used any longer, or so I was led to believe; most tonearm designers favor placing the null points toward the outer groove for maximum fidelity. The various geometrys will affect skating force insofar as the optimum tonearm offset angle will be different for each geometry. I'd have to think more about that, though.