[Kontact]

Grease is okay, carbon paste correct for carbon frames, and anti-seize is the right stuff if you're clamping or threading Ti to another medal.

I do not know if there is such a thing as Ti to Ti galling, but anti-seize is cheap enough to make it not worth researching. Antiseize IS grease, so the weatherproofing aspect isn't something you lose compared to regular grease. Antiseize is a poor lubricant compared to grease, but is fine for any static grease application (posts, threads, splines, etc).

 

[Kontact]

I used ti prep on my Blacksheep's ti seatpost and ti frame.
Bad mistake.
The post and seat tube bound together and we had a hell of a time getting them apart.
Recommendation from the importer here was to use Copper Slip.

I very much doubt that "Copaslip", a copper based anti-seize, and "Ti Prep", a copper based anti-seize are much different.

 

[Kontact]

No idea but I know that ti-prep (which is what I believe the LBS used) did not do the job.

That may be, but some other compound would have probably faired just as poorly on your particular post/frame combination. Blaming the compound is misplaced - there's nothing really better than copper based anti-seize of any brand. Nickel based is the only one that might be "better", but only at high temps.