Officially, OSC command sent to any parameter Clip Tab are 'context' dependent. This means they are always applied to whichever clip is currently highlighted in the tab.
This is reflected when you switch between 'deck' and 'layer' focus. For both options, you'll see that parameters in the Clip Tab are addressed with /activeclip/....
When you address the Layer Tab, switching between 'deck' and 'layer' will show different addresses. /activlayer/... for 'layer' focus, /layer1/.... for 'deck' focus. This means you can address either the active layer, or a specific layer.
As .lov. correctly mentions, this is the official behaviour, and it's documented both in the manual and represented when entering OSC Mapping Mode.
Un-offically, you can send OSC to individual clips as well. /layer1/clip3/video/scale/values will always address the scale of clip 3 in layer 1. Also /activelayer/clip3/.... will work to address the third clip in the active layer.
This behaviour is undocumented, and not officially supported. But it's pretty safe to use, and shouldn't cause any problems.
