1. have from time to time had the bibb washer and sometimes valve seat
changed on hot side due to slow drip from hot side of a standup shower (not witha tub) with separate
hot and cold sides -- and the leak had stopped. (has always been hot side)

2. cold side was changed about 6 years ago but so far it was the hot side.

3. when the stem was taken out, the hot side bibb washer (washer at the end of the stem) was either badly worn or
had disintegrated, which I realize does happen.

4. however, with recent leak, yesterday when they took out the stems on both
hot and cold side, the bibb washer was not badly damaged, though I realize it
does not have to be for leak to happen - am just pointing out difference from in the past.

5. they changed the valve seat and wrapped plumbers tape around the valve seat threads
that screw into valve body - I realize not all approve of this, but noticed that the
valve seat from the cold side still had some of that tape on it from 6 years before.

(it was the same person who did the work 6 years before as did the work yesterday,
but they have not done it in between, that was someone else who I know and trust)

6. long story short, the leak has not stopped and in fact has become worse since they
did this work. I have tried tightening the handles a lot, and then backing off some
but does not help.

7. The person who did it is not a licensed plumber but does do this work all the time
and seemed to know what they were doing. I am guessing that 6 years ago they solved the problem then but can't remember.

8. When I pointed out to them that the leak had not stopped, they became agitated and angry,
and said they thought there was a crack or problem in the valve body itself,
which I realize would mean that wall would need to be opened up and all sorts
of major work and the shower is a self enclosed one piece one.

9. the original leak was not a lot and varied based on just how we tightened and retightened
the faucet handles after each shower, and I probably should have let it be.

===> Questions

1. is this scenario possible, that this time, its not the bibb washer or valve seat
but problem with the valve body or something else ?

( I do recall long ago getting an estimate from someone else on a similar leak and they
said without looking at anything that it was valve body and big
job, but back then it turned out just to be needing to change bibb washer and valve seat.)

2. should I get someone to at least take out the stems and examine
placement of the washers and to take out valve seat and see if their
work was ok and then put back in just to see if the work yesterday
was not done correctly ?

3. for standup showers, is there a concept of grinding the valve seat area, or is that
just for sink type faucets ? I have not seen this referenced in postings or articles
about repairing shower faucet stems.

Sorry for a long post, am not able to do the work myself but on low income/unemployed
so this whole thing is stressful, especially with them getting so angry and upset,
besides the leak getting worse (I would have settled for it just being the same amount
of leak as before had I known about this outcome)

Thanks for your advice.