The other isomer is zuclomiphene and it is primarily responsible for Clomid's estrogenic properties. As such, this is the isomer that is most of interest when it comes to figuring out the time for Clomid to "clear out of your system." And, unfortunately, zuclomiphene has the longest half life - significantly longer - and this is why estrogenic side effects can linger for quite awhile after quitting Clomid. So what is the half life of these two isomers in Clomid? This question was probably most definitely answered in a study on women. 
The decay of a mixture of two or more materials which each decay exponentially, but with different half-lives, is not exponential. Mathematically, the sum of two exponential functions is not a single exponential function. A common example of such a situation is the waste of nuclear power stations, which is a mix of substances with vastly different half-lives. Consider a mixture of a rapidly decaying element A, with a half-life of 1 second, and a slowly decaying element B, with a half-life of 1 year. In a couple of minutes, almost all atoms of element A will have decayed after repeated halving of the initial number of atoms, but very few of the atoms of element B will have done so as only a tiny fraction of its half-life has elapsed. Thus, the mixture taken as a whole will not decay by halves.