Pearl Tiger Theatre Stack Behaviour in Rec by Channel Mode

[RBWB]

Despite reading the manual I'm unable to resolve the following question:
I have put the desk in tracking mode (ie Record by Channel) & programmed a series of dimmer cues (ie HTP channels) into the console in Theatre stack mode. On playback I would expect a tracking console to only output the changes between cues. Take the following 2 cues:
Cue1: 1@10
Cue2: 2@10
On replaying Cue2 I would expect both 1 & 2@10 on the channel outputs view especially since I didnt explicitly record a blocking cue of 1@0 in Cue 2.
But replaying Cue2 just puts 2@10. I did press 'clear' before setting up & recording cue2 - but thats not the same as explicitly recording 1@0 is it? Even if I approch it a different way by inserting cue 1.1 containing 2@10, when I replay back cue 1.1 ch1 is still 0.

Where am I going wrong please? Does the tracking mode of Pearl behave
like a tradition tracking desk?
I accept that performing a similar test using moving lights in 'rec by channel' mode works perfectly as expected

Thanks in advance for your advice

[niclights]

Theatre stack is not tracking. There is no tracking function in the Pearl Classic software. Record by channel in all consoles means you record only what is in the programmer.

Tracking is only available in Titan Expert/D4 cuelists.

[RBWB]

Many thanks for the fast, efficient reply Nic