A tad confusing
Your question re: player's advantage is a little nebulous. When you play proper BS, you have to play FLAT to maintain the theoretical adv.(which in this case is neg. and in general is about .5-.6%. What does set this neg. pct. (assuming perfect BS is being played) occurs even before you sit down to play. i.e. the table rules... This is what predetermines yor mathematical long term fate. This will tweak you -pct. up or down by various house,table rule adjustments. Some pos. adjustments or variations would be those such as DAS, s17,Sur, resplit Aces, DOA etc. Negative variations would include such rules as D10, no Sur, h17, no DAS etc. To sum it up, playing BS presumes a flat bet always (before doubling and splitting) and there is no controlling indicator to change bet size.
When talking about the .5% adv. per count you are assuming a count strategy that's in place which signals the player to increase/decrease his bet size and yes, more or less this indicator reflects(true count) about a .5% increase in the players adv. as it rises point by point.
Lastly, betting stategies alone will NOT give you any advantage unless the underlying game you are playing already is in your favor, which BS is not. Hope I answered your question as I was trying to interpret what you were really trying to get to.