Lennox XP25 Balance Point

Just had an XP25, SLP98V, and iComfort tstat installed. The balance point settings are disabled in the tstat. The installer said the tstat will control the changeover to the furnace during one conversation. In a separate conversation he said he likes to set the balance point to 30.

Which is correct? Is the tstat smart enough to make the changeover without balance points?

Thanks.