Probaly taking a well deserved bank holiday break!!
Yes, looking at it as pairs in row three certainly gets the right result, but is it for the right reason I ask myself?? My understanding of the logic of pairs is that if the cells of the pair are "contaminated" with (an)other candidate(s), then these contaminates can be deleted, as long as the members of the pair do not appear outside the two pair cells.
Bingo, you are dead right, I have looked at it again, and the 168 16 pair meet the above criteria! I was not looking clearly enough, and concentrating in the 138 38 supposed pairing in that row, which obviously does not qualify as a pair as it stands, as there is another candidate 8 in the row. Woolly thinking strikes again! many thank for your help. I'm off for a very long weekend now to give my brain time to recover, and I am determined not to look at another Su Doku until I get back!
![Smile :D](http://forum.enjoysudoku.com/images/smilies/icon_e_biggrin.gif)
Have a good weekend