Creating a TautomerEnumerator instance is very slow. Is this expected or should it be improved?

[kienerj]

Simply creating an instance is very slow:

Therefore one has to take extreme care it's never called inside a loop. Like if you are creating a function to be reused possibly in a loop, the function must be designed in a way that the enumerator can be passed in or else one ends up with spending 99% of the time on instance creation.