There are two scenarios here:
Scenario 1: Very bad answer gets deleted
Here we assume that the user was attempting to answer the question, but it was bad enough to get deleted. That's normally pretty bad. The assumption when an answer gets deleted is that it is not salvageable by editing. I would assume this is normally most often the case when the answer is so short as to be unintelligible. Like others have mentioned, one approach here would be to edit the answer and flag for moderator attention. I'd propose though that it would be as good or better to just submit a new answer as it requires no moderator intervention, and saves their attention for other things.
Scenario 2: Non-answer gets deleted
In this case, what was originally provided never attempted to answer the question. It may have been spam, or more often a comment submitted in the answer field. I believe this was the case with your original answer. In such cases, it doesn't make sense to resurrect the old answer. It was never an answer to the question. Any votes or revision history contained in it are irrelevant. If you previously provided a non-answer and it gets deleted, its ok to let it go and start fresh with a new answer, which you have already done in this case. Since you now understand the rules about where to comment, presumably this will be the only occurrence of this issue for you.
As a side note, my recollection is that reputation loss is refunded for downvoted answers that get deleted. That would be another fringe benefit to starting fresh, if previously provided an non-answer and later wanted to add a real answer.