I'm used to segment starts and ends being a bit wobbly across companies/GEDmatch, but this example I just saw at 23andMe seems a little extreme:

Peaches matches Dad at 115-123, 14.9 cM, 983 SNPs.
Peaches matches me at 112-127, 23.2 cM, 1587 SNPs.
Peaches doesn't match Mom.

Can anyone explain why I would show up as sharing so much more with Peaches (in Mb, cM, and SNPs) than Dad does? Is it just the weirdness of trying to calculate X matches and make corrections for male/female? Dodgy algorithm at 23andMe? Dad's test having some strategic no-calls?

Thanks!