Was the incision separation on my anchor lift/implant preventable or inevitable, given that it is common with this procedure? (p

Congratulations on having undergone the breast reduction procedure.  Unfortunately, as you mentioned these types of delayed healing problems are not uncommonly encountered, especially at the "T junctions" (related to blood supply and tension concerns). These wounds go on to heal through a process of contraction where the tissues heal from the sides towards the center of the wound; this process usually takes several weeks to occur, depending on the size of the wound. Occasionally, removal of unhealthy tissue (debridement) and/or removal of exposed sutures, may expedite the healing process.   Without knowing much more detail (really known to your surgeon only), online consultants will not be able to help you with your question regarding predictability...Best wishes;  despite the separation/wound it is most likely that you will be pleased with the longer-term outcome of the procedure.

Unfortunately the situation you have experienced is not uncommon after Anchor Incision Breast Lifts or Reductions. However, as your photographs show, you have progressed quite well and with time the scar will fade or can be easily revised (at 1-2 years post surgery). This separation occurs because the blood supply at the corners of the "T' can be precarious even in the best circumstances. Fortunately long term serious consequences (besides the wider scar) are rare. I wouldn't beat yourself up about what you might have done or could have done. Complications such as this are usually bad luck and had nothing to do with your activity, unless you did something really extreme and crazy. Keep following up with your PS and be reassured you are going to do well.