Essentially that is what I am doing. However, it is not quite as simple as I thought.
If there is a marriage event for the deleted person then TreeShare does not directly add it back it.
Initially I was adding it back it when running a resync on their spouse but I found that TreeShare added a second copy of the marriage event to the spouse.
In the end my solution is to:
go to the spouse in Ancestry
make a change (normally just edit, add a character to the description, save, edit (again), remove the new character, save)
resync the spouse but update the marriage rather than add it because Ancestry has put the event on the spouse but without the source.
I also find that TreeShare affects individuals connected with that deleted and resync'd individual which then involves more clicks to then show them as unchanged.
The good thing is that new hints appear on Ancestry, which of course then need resyncing!
It is a shame that this is so long-winded. I suspect we are back to the problem that TreeShare is a new feature which is slowly evolving to cope with problems imposed by Ancestry.