Don't worry, you're in Balmain, so you can do a lot worse (like The Bridge... Coming soon). The Cat and Fiddle is one of those comfy places where you'll get a warm reception from the bar staff, more out of relief that they're finally being frequented by someone who resembles a productive member of society.
The patrons aren't gruesome in the harsh sense of the word, more like the Newtown sense of the word. "Mongrels" - in a quiant, bohemian kind of way. Good for a laugh in any case. Just remember, there are the real owners of the place, and the "unofficial" owner, also known as the housing commission twit who thinks that drinking at the Cat and Fiddle day in, day out, means he "owns the place". Just laugh in his face, it's what everyone else does.
In spite of perceptions of a pub with some serious upkeep to do, there is a surprisingly quality bistro with a lone, accommodating, and flexible chef who takes pride in his work. His menu is fairly priced, his cooking always a satisfying affair. On Friday nights you will usually find a band throttling out some ear-splitting racket that sounds like a shrieking cat combined with an untuned fiddle, hence the name of this joint. Avoid at all costs, and go sit amongst the cross-section of society that fills the main room.
Other than the bistro, this place is good for a few quick ones before heading off to somewhere with a bit more substance. It is generally the refuge of the aforementioned local scum, who find the option of putting their own takeaway beers behind the bar, to be produced upon request, an invaluable trait for any pub. In spite of this, I'm never averse to moseying on in and pumping back a few frosty ones, and this place makes you feel guilt-free when looking down on the common man with an unreserved contempt.