I have a group of 3 dimmers, which I can control just fine.
However, one of the dimmers have very weak lights in it.
Can I somehow define the dimmer - or the group - so that that one dimmer gets double the % light ?
Not in a direct way (sort of).
One option: use a proxy item, i.e. instead of grouping the “real” dimmer item, use another (unbound) dimmer item. Then build two rules to “forward” commands and updates (the two directions, in and out) to/from the real item to the proxy item. In the rule use whatever you want to “enhance” the dimmer curve, add a value, multiply… whatever.
Another option: more or less the same, but now use the link profile to insert the rule directly into the data path.