Block and punch with same hand
Dear All
Gassho
Dave is entirely correct, dan-zuki means block and counter with same hand.
I asked one of the 8th dan instructors about this technique in Paris at the 2001 Taikai, as I really struggled to see the point of it and uchi-age dan zuki which is so similar as to make you wonder about the duality.
He explained that it was a technique where the other hand was engaged ie holding your wife's hand, holding a fu'kll pint of beer or being held and restrained by a 2nd attacker.
He also explained that soto uke or uchi age was dependant upon distance and space in which you, the defender, have to manouvre, he stated that uchi age is far more close proximity but that both techniques have to be done with little or no footwork just tai sabaki.
He made us practice from hiraki with front hand striking and taigamae with back hand doing all the work, he also made someone hang onto our other arm so we couldn't use it or move.
Interestingly he also said that ren han ko should not be with the "other" arm but with a foot or knee strike as you have to assume that you still have only one arm to deal with the attacker and finish them off.
Try it, you might like it, I did and I now understand and value this hokei dearly.
Kesshu