Originally Posted by
Crescent Cycle
To be fair, saddle setback, also known as seat tube angle, has some effect on how relaxed a bike can be fit, even with setback posts. Lemond advocated relaxed 72-73 degree STAs for his idea of a proper fit. Stack, closely correlated with head tube length, will also have an effect on how high you can place the handlebars if you want to run with a high rise stem and max spacers.
Saddle setback is not the same as seat tube angle; they're related but not interchangeable in any way. Also, 'relaxed fit' is not the same as relaxed geometry.