Thanks for your replies Cephalad (and EctoRune), I have a rudimentary understanding of Statitsics having a Diploma in mathematics, seemingly others do not My post was out of interest as something I felt I had observed empirically but had no sound evidence for, and wondered if anyone else had looked into it substantively (to save me the effort). Anyway I continue to collect the data!
For conspiracy theorists, or anyone interested...
My sample is still too small... but now 71 searches...
now 26 out of 71 which as with the original post is still around 37%... (although last week it was a record 10/23=43% ... acceptable ) again for the fewer coal searches it is 12 out of 27 (44%, was 45%).
Looking forward to a run of 8 fast to bring it to an even keel.
on the karma front my 2.5 (I added one midweek) explorers recently returned 3 nords in 8 days, and ages ago my first ever sftr yielded a white castle. I guess my skiving improved Jolly Geologist is just payback.