https://www.google.com/webhp?sourceid=chrome-instant&rlz=1C1VFKB_enUS595US595&ion=1&espv=2&ie=UTF-8#q=when%20did%20bonds%20start%20using%20steroids

Not sure what you are talking about regarding the whole when everyone who was following him. It is common knowledge that it started after the 1998 season.
So no big deal right? After Bonds turned 34 he went on to hit 352 more home runs.

During the point in his career when he should have been regressing he was hitting HRs out of a pitcher's park at a rate unseen.

Then you explain it by a swing change? Honestly that is pure comedy gold. Too bad all of the Baseball Writers of America don't agree with you and your "swing change" theory or Bonds might actually make it to the Hall of Fame.