Well since the thread has achieved necro status, I might as well post an update to this:
I had two small warts on the back of a finger (middle) that were about 3 mm apart. I had another two small warts on the back of the same hand but they were much further apart. My doctor hit them all with liquid nitrogen, told me they were so small that it should only require one treatment.
The two blisters on the back of my finger grew into each other (the blisters started out separately but then merged into one big blister). And the entire thing grew back as one big wart covering the entire area that was previously blistered. The other two warts on the back of my hand came back, too (but separately).
Weird thing. I left the warts alone for several more months, then started to notice the warts were changing. Over approx. two week period, the warts became sorta inflamed looking, thicker, more reddish, with scaling tops. Then they started to itch. At first I thought, the virus was trying to actively spread and infect other cells or something. I had a doctors app. the next week, anyway, so I showed it to the doctor when I was there, who referred me to a dermatologist after agreeing they didn't look like "typical" warts should.
By the time I saw the dermatologist two weeks later, the warts had diminished or receded to nearly being flush with the surrounding skin (when I went to the doctor, the warts were raised and inflamed). The dermatologist said it looked to him like the warts were healing, my immune system had finally gotten wise to the virus and was clearing it, hence the 'inflammatory' phase that I previously observed. A month later, they were gone! Except for some light scarring from the prior attempt to freeze them off, which now is unnoticeable to anyone but me.
So apparently you can have warts for several years without much attention from your immune system, then the immune system can just kick-in and start clearing the virus.