You're welcome. Yeah he might be very territorial. The flaring isn't so bad but what can happen over time (this is what I read at bettysplendens) is that they 'blow' their tail. It looks kinda like a flag that got caught in a high wind, all tatters and strings hanging.
That's what happens to Tango's tail and why I put a background up. Whiskey flares all day too but he doesn't blow his tail. Maybe because Tango's a veiltail it affects him more. I dunno.
Try different things. See what works best for him.