Our patio pot tomatoes have done very well, both cherry & medium sized.

They've both exhibited the "splitting" you talk about, but only when they're ripe. So we take this as signifying they're ready to remove. Taste is good.

As for water, we've been doing it daily, sometimes twice, throughout the summer drought here on the South Coast. No lack of water, or irregular watering. Given them regular "Tomorite" feed - say once a week.

( And of course, it depends what you mean by "splitting" too - what we're talking about is more like a "smile" across the tomato surface, not a chasm )