I realise that this subject gets huge forum time so apologies for starting it up again but it really is personal to your own circumstances and I would appreciates some views please.
Been playing 12+ years losing player overall. Mainly played MTTs but now spending more time playing cash at micro levels online.
I have a Poker coach but he doesnt coach cash and is wise enough to admit that.
My problem (well one of them anyway is around that old chestnut variance) I can never be sure if my results are good / bad / indifferent / to be expected normal etc etc.
Current state of play is:
Full ring 1/2 cent NLHE multi tabling from 4 to 16 but now settling on 6 as my optimal number.
15202 hands so far bb/100 -5.24 Currently $-15.96 down Highest +$6.21 lowest -$22
The questions :-)

How many hands before you really have a good idea whether you are losing / break even or winning.

When people talk about experiencing a downswing of 20 buy-ins do they mean they are down over 20 buy-ins or that they are 20 x the buy-in down!

What is the largest downswing that is reasonable and still recover to be a winning player

Finally the most important question to me. I am wondering if my biggest mistake is playing for too long when I am losing and not long enough when the going is good!!!

Any constructive comments would be much appreciated