CC - you have an unstable joint there between your collarbone and your sternum. As long as the Docs say you're stable and you should continue with activity, keep plugging away. But this could easily take up to a year to completely scar up and stabilize so that it doesn't get irritated with certain activities. And activities that consistently give you sharper pain should be avoided because you will start to compensate somewhere else and end up with a sore shoulder or something. If it's an ache and you know you're holding form through your stroke (ask a knowledgeable person to watch you) then go ahead and keep doing it, it may actually help things along.
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2007 Look Dura Ace
2010 Custom Tonic cross with discs, SRAM
2012 Moots YBB 2 x 10 Shimano XTR
2014 Soma B-Side SS