This is the latest from the Yahoo board…
http://groups.yahoo.com/group/FRCtech2002/message/309
Message 309
“A) GM20 does NOT exclude interacting with the lower surface of the upper deck or, conversely, interacting with the upper surface of the lower deck. However, if by interacting with the lower surface of the upper deck, for example, you apply enough upward pressure to it to allow the goal to be pulled or pushed, then FIRST would consider you to be attached… which is disallowed. In a nutshell, incidental interaction, such as to “sense” where the surface is or with robot arms extending/retracting in that area, is allowed and expected.”
Message 207
“Can a robot deliberately interact with the bottom of the upper plywood platform of the goal (as long as it does not cause damage)?
A) No. FIRSTsnow”
Message 120
“To be clear, see rules GM21 and GM22. A robot could react against the lower surface of the upper plywood if it did not attach to it and did not present a risk of tipping the goal over.”
Message 207 and 120 are definately contradicting each other. Rules GM21 and GM22 do not state rules, rather examples of what is acceptable or not. I think FIRST needs to set rules (standards) which clearly differentiate acceptable from unacceptable, rather than arbitrarily giving examples of what is acceptable and not.