A strict no no. If you have this tendency, it may
be better to avoid a yoga retreat altogether. It is not uncommon for
people with such attitudes to experience injury. A group setting has
the danger of making you uncontrollably comparative, in comparing
postures efficiency and capability. Yoga is NOT a competitive sport.
In fact, the best benefits of Yoga can be had by understanding
"your" body and not torturing it.
While this is
fairly well known, it is difficult to not fall into the trap of
comparison given our societal upbringings.