if price moves up slowly and hugs that peak line on the MACD its...

if price moves up slowly and hugs that peak line on the MACD its a slow grind up.
If it breaches that top line its a blow off.
if it shifts up quickly and taps, price is likely to turn

The current S&P500 Action shows price rising relatively quick compared to the movement of the 200 ema (i.e. a tap an run type scenario).

I think of this as a bollinger band type scenario or where price has moved to far away from mean price.