complex schomplex.e-juice is just a glorified nicotine inhaler.
PG and VG are not used to enhance our vaping experience.
they're used because because they are good for dispersing subtances
very evenly and keeping them dispersed for a long time,
and are generally considered safe.
the vapor is just coincidental and i'd say good side benefit.
any molecular bond if any(i doubt there is any considering the ingredients used.)
would occur during mixing.you do not want any complex uncontrollable molecular bonding
going on.what if it recombines into strychnine?
the ingredients used are ones known to resist combining to form complex molecules.
mild heating is just agitation.high heating equals cooking which e-juice is not.
and don't forget the single largest component of the vapor is air.
the air around us.air temperature,humidity,and barometric pressure
along with the condition of your coil (new,just cleand,a week old) affects
the viscosity thus the taste of the juice.

regards
mike