Andreas The FTDNA ICW report uses the same criteria for a Match that FTDNA uses for your Match list: 7.7cM segment, 20cM total, etc. So all of your ICW list with Match A meets this criteria for you (everyone on the ICW list is already listed as a Match for you) AND each person on that ICW list meets the same criteria for Match A (is already on the Match list for A). So no one is talking about matching based on 1 or 2cM. Every shared segment over a threshold (7.7cM, etc for FTDNA) has to be somewhere. When such segments for Matches A and B significantly overlap on the same chromosome in your spreadsheet, they are on the same chromosome OR on opposite chromosomes OR one or both are IBS. If they were IBS or on opposite chromosomes they are rarely ICW. Using the 7.7cM threshold, the FTDNA ICW method for triangulation works a very high percentage of the time. Getting a confirmation from either A or B make it as firm as any other TG. I don't see 1cM segments in this process. Jim - www.segmentology.org > On Dec 13, 2015, at 12:40 AM, Andreas West via <genealogy-dna@rootsweb.com> wrote: > > Hi everyone, > > > was just stumbling across a post on WikiTree forum on DNAGedcom being able to > triangulate data from GEDmatch and FTDNA. Leaving GEDmatch out for this thread > (I think the OP refers to the paid tier 1 option which gives access to the top > 200 triangulated matches and downloading that screen result - please correct > me if there is another way) I want to question that remark about FTDNA. > > My assumption is that ICW (which isn't triangulation, can't repeat that often > enough as there are still people out there who don't understand the difference > or that there is one to start with) means that it includes all those 1cM > matches (and larger) that FTDNA reports as a minimum criteria. > > Can someone confirm this? > > That makes the ICW tool even more worrisome if it's true as it's not even > clear if a triangulated segment of only 1cM (or 2cM for that matter) is indeed > an ancestral segment, triangulation or not (I refer to various discussions we > had here and on other email lists about this - no need to start that > discussion again until we have more proof). > > Andreas (WEST) born BASSO >