Zeppelin 0.6.2 Angular. Trying to watch a variable before binding first is not going to work

ZeppelinAngularBindWatchChange.scala

// Demonstrates usual z Angular bind/watch/change scenario (watch is working)
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
val logger: Logger = LoggerFactory.getLogger("MyZeppelinLogger");

logger.debug("START");
z.angularUnwatch("ax4_var")
z.angularUnbind("ax4_var")

logger.debug("Setting ax4_var=Init before watch");
z.angularBind("ax4_var","Init before watch")
logger.debug("Before configure watch on ax4_var");
z.angularWatch("ax4_var", (before, after, ctx) => {
    logger.debug(s"Watch (before, after, ctx) triggered. Old value=$before New value=$after");
})
logger.debug("Watch configured");
logger.debug("Changing ax4_var='Change after watch configured'");
z.angularBind("ax4_var","Change after watch configured")
logger.debug("FINISH");

//[DEBUG] 2017-03-17 00:16:27.308 [pool-2-thread-10] MyZeppelinLogger - START 
//[DEBUG] 2017-03-17 00:16:27.882 [pool-2-thread-10] MyZeppelinLogger - Setting ax4_var=Init before watch 
//[DEBUG] 2017-03-17 00:16:28.267 [pool-2-thread-10] MyZeppelinLogger - Before configure watch on ax4_var 
//[DEBUG] 2017-03-17 00:16:28.815 [pool-2-thread-10] MyZeppelinLogger - Watch configured 
//[DEBUG] 2017-03-17 00:16:29.076 [pool-2-thread-10] MyZeppelinLogger - Changing ax4_var='Change after watch configured' 
//[DEBUG] 2017-03-17 00:16:29.435 [pool-24-thread-1] MyZeppelinLogger - Watch (before, after, ctx) triggered. Old value=Init before watch New value=Change after watch configured 
//[DEBUG] 2017-03-17 00:16:29.671 [pool-2-thread-10] MyZeppelinLogger - FINISH 

ZeppelinAngularWatchChange.scala

// Demonstrates an attempt to start watching variable without binding to it first: watch/change scenario (watch does not work)
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
val logger: Logger = LoggerFactory.getLogger("MyZeppelinLogger");

logger.debug("START");
z.angularUnwatch("ax4_var")
z.angularUnbind("ax4_var")

logger.debug("Before configure watch on ax4_var. No binding on ax4_var set yet");
z.angularWatch("ax4_var", (before, after, ctx) => {
    logger.debug(s"Watch (before, after, ctx) triggered. Old value=$before New value=$after");
})
logger.debug("Watch configured");
logger.debug("Seting binding on ax4_var='Initializing ax4_var after watch is configured'");
z.angularBind("ax4_var","Init after watch")
logger.debug("FINISH");

//[DEBUG] 2017-03-17 00:33:33.424 [pool-2-thread-7] MyZeppelinLogger - START 
//[DEBUG] 2017-03-17 00:33:34.101 [pool-2-thread-7] MyZeppelinLogger - Before configure watch on ax4_var. No binding on ax4_var set yet 
//[DEBUG] 2017-03-17 00:33:34.621 [pool-2-thread-7] MyZeppelinLogger - Watch configured 
//[DEBUG] 2017-03-17 00:33:34.801 [pool-2-thread-7] MyZeppelinLogger - Seting binding on ax4_var='Initializing ax4_var after watch is configured' 
//[DEBUG] 2017-03-17 00:33:35.219 [pool-2-thread-7] MyZeppelinLogger - FINISH