Why do you use Campden tabs in secondary?
I should say that I usually only do this when kegging, and I do it mostly for big beers like Belgians and scotches. It kills any yeast in suspension and any rogue bacteria (from the Gelatin addition) that may have inadvertently crept in. I should also mention that have been know to use Potassium Sorbate on occasion for the same purpose. The difference is the Potassium Sorbate inhibits yeast and does not kill it. Big beers (final gravity above 1.030) will have lots of sugars in suspension which bacteria and wild yeast tend to go after. It is just a precautionary step. I have thought about doing it for all beers and using fresh yeast when bottling, but that drives up the cost of the beer.
What is your "typical" secondary and tertiary schedule for Belgians?
As I'm sure you know, it would depend on the yeast and the size (OG) of the beer for the primary. Conservatively I would say I have waited up-to a month in primary depending on the OG of the wort. The secondary is usually only about 5-7 days in the beer fridge at 34F to get the yeast to fall out. The tertiary step or cold conditioning is usually for about 90 day's (like a Lager), but that also depends on how big the beer is. I would say that a "standard" Belgian could be ready in 30-90 days. Doubles depending on the grain bill could be 30-120 days. Triple's are ready when they are ready, I don't put a time frame on them. I have a Belgian Triple that has been going for almost 6 months now and it is still not ready.
I ask because a friend uses his same (lengthy, but successful) lagering/cold conditioning times on belgians that he uses on hybrids. I've wondered whether he is losing ale aroma over that time.
Sugar additions in Belgians need time to age, also Belgians are not hoppy so you are not loosing anything there. As far as hybrids go, that would depend on a lot of factors like grain bill, hops, and if any sugar additions were added. There is nothing wrong with waiting IMO. Typically beer gets better with age right? ;D
Cheers
Preston