The easiest way I found to force single touch across an entire app is to set it using a theme:
<style name="MyTheme" parent="@android:style/Theme.Holo.Light">
<item name="android:windowEnableSplitTouch">false</item>
<item name="android:splitMotionEvents">false</item>
</style>
Manifest:
<application
android:label="@string/app_name"
android:theme="@style/MyTheme" >