The instructors where I learned would not do more than two lessons a day as they reckoned with briefing ,hour's flight,then debrief with a break in between lessons was enough.
I think that was correct,for me anyway
I flew Friday,Saturday and Sunday weather permitting,so some weeks got in 6 hours and it took me from August 2005 to May 2006.
total 53 hours,but it isn't a race
Lister