Even if theoretically possible, there can always be a risk in missing the connection. I say connection - but actually it is not. Aegean will likely not sell you such back-to-back flight, even if theoretically you were to be within MCT. As such there would always be a risk. If you are happy to accept that risk and the possible consequences, then go for it - otherwise it may be better looking for a method that allows for a little more time in between flights.