Dieter: Just an observation. Most of the rengos that go on in this place slow down in the middle game. Seems like many players are keen on participating in the opening, but much less in the middle game. It is also the part where one can much less discuss intuitively. Tactics are heavily involved. Mistakes are often blatant. It runs parallel with my experience in game discussions. Everybody finds the opening interesting, the middle game complicated and the endgame rather boring.
QWerner: Right. I realy have problems to get some informaion about the middle game on SL. Per example there is almost nothing about how to use thickness or good reduction play. It would be great if there would be some sides onj SL about that.
Velobici: Thoughts on the phases of the game and players of various strengths.
Endgame play is calculation. Good players can determine the order to play various endgame sequences. Errors can be quantified exactly. Great players are frightening, even to other professionals, at doing this (e.g. The Computer aka Ishida Yoshio.)
Middle game play is tactical. Again good player can demonstrate superiority in sequences that are played. Sequences can be quite branched or long. Errors can be assigned some value of points gained or lost.
Opening play is perhaps the least constrained. Many possible strategies can be played. Often a professional will comment with "best", "playable", "its a game", and other words indicating that a variety of plays may be considered. Joseki dictionaries can be consulted for the tactical issues as well as seeing what possible strategic results each joseki element leads toward or precludes.
These considerations act to discourage folks from playing in the rengo as the game develops. As play continues, it becomes easier to identify outright errors. Who wants to be the person that makes the losing move?
Bob McGuigan: Another factor relevant to the rengo situation, I think, is the fact that in the opening it is possible to play very well when you are a relatively weak player simply by following patterns from pro games, for example. But in the middle game there aren't many patterns the weaker players would recognize, so mistakes are easier to make.