Have had two titanium frames over the past 10 years and loved them both. One is still in service and equipped with alloy parts. Seat posts are coated with white lithium grease before inserted into the seat tube. BB cups and headset cups the same. Yeah, not the fancy grease, just good ol' lithium, the do all grease. lol. Was a huge proponent of Phil, and it is what I use for bearing surfaces, but for the simple task of preventing corrosion, lithium grease does the job. Yet to see any corrosion on the aluminum or steel bits.
From a shop mechanic point of view, we routinely get old 70's era Schwinn bikes in for work that are rusted like crazy on the outside, but the stems and posts pop right out because they were coated in white lithium grease when originally assembled.