My take is that it all depends on what's being attempted.
Lifting that rock, I might just say five folks with at least a ten Strength can lift it. Done.
Busting down a door, well, the main person might make a Strength check -- but the "assistant" might need to make an Agility check to help, because that door is in a narrow alcove, and the more important issue is "can you even squeeze in and help in any effective way?".
The circumstances effect how it's resolved.
But the baseline method could be anything from d20 standard rules to whatever you prefer at your table.
Gnome Boy (a.k.a. "Jon") • DCC play-tester @ DDC 35, Feb 2011. • Beta DL 2111, 7:00 AM PT, 8 June 11.Playing RPGs since 1977
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