This subtitled is displayed as three lines.
<Subtitle SpotNumber="19" FadeUpTime="0" FadeDownTime="0" TimeIn="00:04:13:141" TimeOut="00:04:16:065">
<Text VPosition="14" VAlign="bottom" HAlign="center" Direction="horizontal">–These are two lines. </Text>
<Text VPosition="8" VAlign="bottom" HAlign="center" Direction="horizontal">
–
<Font Weight="bold"> But DOM sees and displayes it as three.</Font>
</Text>
</Subtitle>

When changed to this:

<Subtitle SpotNumber="19" FadeUpTime="0" FadeDownTime="0" TimeIn="00:04:13:141" TimeOut="00:04:16:065">
<Text VPosition="14" VAlign="bottom" HAlign="center" Direction="horizontal">–These are two lines. </Text>
<Text VPosition="8" VAlign="bottom" HAlign="center" Direction="horizontal">
–<Font Weight="bold"> But DOM sees and displayes it as three.</Font>
</Text>
</Subtitle>
it is displayed as two lines. I think this is incorrect, as per specification:

"Multiple lines of text should be handled by multiple Text elements." (section 2.10 here: http://www.deluxecdn.com/dcinema/reference/ti_subtitling_spec_v1_1.pdf )

There are two possible solutions:
a) Throw an error "newline in Text element deceted" or something like that.
b) Swalow newlines when consuming text elements.

I am not sure this is precisely what happens. When playing around with the XML, inserting newlines here and there, IC ould not for example produce a 4line subtitle. Also, the text "At least one of your subtitles has more than 3 lines. It is advisable to use no more than 3 lines." when running checke before DCP creation got displayed only sometimes.