A magus experiments on a new spell he is inventing (a spell to change into a wolf). Following the example in the book, the experimentation yields a major side benefit, allowing him to also speak with wolves while in wolf form.
Can experimentation change the final level / arts of the spell (e.g. in this case, one would expect an extra Intellego requisite and a boost in level)?
When a second magus uses the lab text of the first to re-invent the spell (without experimentation), does he get the major side benefit obtained by the first magus?
If so, what if the second magus himself experiments (on the lab text of the first), and gets, say, a minor side benefit as a result? Do the two benefits stack or does the second supercede the first?