Puzzled by 111 markers results

[on the edge]

My understanding of the purpose of the 111 marker test is that it should help to refine matches that have been established through the 67 marker tests.
In our case it appears to have done the opposite, as demonstrated by this specific example: (FTDNA FAQ explanation in brackets)

25 marker GD=2 (2 Probably Related)
37 marker GD=4 (4 Probably Related)
67 marker GD=6 (5-6 Related)
111 marker GD=13 (>10 Not Related- The two men are totally unrelated within the genealogical time frame on their direct paternal line.)

The above matches are between two people with the same surname with a supposed common ancestor likely to be more than 10 generation ago.
I am obviously not questioning the results themselves but I wonder how much credence should be given to the FTDNA interpretations as per their FAQ pages. Are we to take the 111 FAQ as gospel and that our previous result matches are just a lucky coincidence, or are the interpretations on the FAQ page too conservative and need to be reconsidered, for some, if not for all.
Any thoughts please.

[nathanm]

My understanding of the purpose of the 111 marker test is that it should help to refine matches that have been established through the 67 marker tests.
In our case it appears to have done the opposite, as demonstrated by this specific example: (FTDNA FAQ explanation in brackets)

25 marker GD=2 (2 Probably Related)
37 marker GD=4 (4 Probably Related)
67 marker GD=6 (5-6 Related)
111 marker GD=13 (>10 Not Related- The two men are totally unrelated within the genealogical time frame on their direct paternal line.)

The above matches are between two people with the same surname with a supposed common ancestor likely to be more than 10 generation ago.
I am obviously not questioning the results themselves but I wonder how much credence should be given to the FTDNA interpretations as per their FAQ pages. Are we to take the 111 FAQ as gospel and that our previous result matches are just a lucky coincidence, or are the interpretations on the FAQ page too conservative and need to be reconsidered, for some, if not for all.
Any thoughts please.

Since the GD keeps increasing with each panel, I'd guess it's just a coincidence that the first ones were closer. However, it also makes a difference which markers differ. If they're faster mutating markers, you can almost disregard them and calculate based on fewer markers. For example, if you differ on CDYa and CDYb, that's almost to be expected. They're the fastest mutating markers observed so far. So instead of say, 33/37, use 33/35.

Unfortunately, the mutation rates for the higher panels, i.e. beyond 67 markers, haven't been published anywhere I've seen. The 111 marker test is still very new, so there probably aren't yet enough testers with public results to estimate mutation rates. I'm sure FTDNA has some numbers they're using internally, from initial tests and everyone who's tested so far. But I imagine it's going to be a while before enough results in surname projects and Ysearch can be compiled into a substantial dataset.

[RCAndrew]

Unfortunately, the mutation rates for the higher panels, i.e. beyond 67 markers, haven't been published anywhere I've seen. The 111 marker test is still very new, so there probably aren't yet enough testers with public results to estimate mutation rates. I'm sure FTDNA has some numbers they're using internally, from initial tests and everyone who's tested so far. But I imagine it's going to be a while before enough results in surname projects and Ysearch can be compiled into a substantial dataset.

Makes me wonder then, if my 3rd cousin, once removed and I both upgrade to 111 markers, will our 67/67 (also have paper trail) match come in at or less than a 111/111 match?

[nathanm]

Makes me wonder then, if my 3rd cousin, once removed and I both upgrade to 111 markers, will our 67/67 (also have paper trail) match come in at or less than a 111/111 match?

It's quite possible, but if you already have the paper trail, it's not really necessary. My take is that upgrading to 111 markers would be for people who match at 67 and want to narrow down the range for an MRCA. Or you just want to be the first person on your block tested to 111 markers.