[lonehunter]

"Is this terrible play of a 8/b hand?"
It depends.

"4th street: W has 7h5s, M has QdTd. M bets, W calls.
5th street: W has 8c7h5s, M has QdTd7s. M bets, W calls."

If W were aggressive they may want to raise on 4th to take the momentum away from M. W would represent 64/75 to M. With a call W is playing it safe.
Raising is more costly on 5th if W is still drawing, which her call indicates. M still only has a pair of Qs at this point and is driving, hoping that W busts on her low. On 5th it looks like W paired one of her low cards.

"6th street: W has 8c7h5s7c, M has QdTd7sAh
W checks and M takes a free card."
Now W has 2 pair and no low. M is drawing to catch. If M bet W would call anyway.

On 7th, W checking usually means they missed. I would bet like M with AAQQ (which he caught on the river), hoping that W had either 2 small pair or a busted low. I have seen many big bets missed on 7th because of this. The check raise sucks, but it is still worth betting because of the times you do scoop.

Just my humble opinion,
-KeithO