On Wednesday, May 24, 2017 at 1:10:12 PM UTC-4, trader_4 wrote:

Update. I hooked up the air compressor and blew it out, going from
the shower head pipe to the tub and then to one sink. Blew out both
the hot and cold sides. Some dirty looking water did come out,
but no sign of any debris. Good news though is the flow rate is
at least double. Easily visible by both the size of the stream
falling and the arc. Tried blowing it again, but it didn't
improve any further and it's certainly acceptable now. Put the
shower heads back on and huge difference, decent flow and pressure
now. So, IDK what was in there, but it sure worked.

I also tried using a heavy gauge piece of stranded wire to snake
it out, but i couldn't get it past the first elbow. I was also
a little nervous that I could wind up with it stuck in there so
given the big gain already, I decided to call it quits.