mikeyd . . . You said …
"The tables had signs saying something like Double only on 11 or less,
but they allowed me to double on soft hands"
What that actually means (in practice) is that you can double on any 2 cards;
however, IF you double a soft hand you may be in for a rude surprise.
When, e.g., your Ace-4 receives a 5 you will have a total of 10, not 20.
They said that you can "only double on 11 or less"; therefore you had
doubled with a total of 5, not 15. You cannot have a total of 20 because
WHEN you doubled you had, (in effect), unwittingly declared your hand
to be eligible for a double, by virtue of its being "less than 11". The Ace
does NOT get upgraded. If that were permissible, then there would be
NO purpose in having the restriction posted. This is absolutely NOT facetious.