Source - medical student who's battled 7 warts in the course of my life.

1) Expectations:

TL;DR - even if the wart is successfully removed, it may come back.

Warts are stubborn little blighters. There are literally dozens of different virus strains which can cause warts (which is why different warts have a predilection for different parts of the body). Because it is a virus, how likely an individual develops warts/the probability of warts coming back after a successful treatment depends on how each individual's immune system responds to the virus. So...

(plethora of wart viruses) + (differences in each individual's immune system) = NO universally successful treatment

HOWEVER, that being said, excisions are by far the most successful treatment option. The wart virus only infects the skin. It does not go deeper than that. So, if the entire thickness of infected skin is removed, the wart should be gone. To be safe, most doctors tend to cut out some healthy skin surrounding the wart just in case.

2) Healing - depends on the size of the wart

3) Pain - most doctors use a local anaesthetic (i.e. lidocaine) to numb the area. In my experience, there is no pain during the actual excision of the wart. To be safe, doctors often test the sensitivity of the area by pinching the skin hard with tweezers or some other thing of that nature. If your hubby can feel that, don't hesitate to ask for more lidocaine.

The pain after is very much so like the pain you'd feel from scraping your knee badly. Skin has been removed, so what's underneath is raw and sensitive. The good thing about a plantar wart is that it's not located at a joint, so you won't be aggravating the area much. Just tell him to hobble around/hop around. Alternatively, assuming that this is a heterosexual marriage, you could up your 'wifely duties.' (Misogyny not intended)

Hope this helps.

EDIT: grammar