Most folks can't 'take it straight' on the tongue (or they're afraid to try)...but I doubt if it really matters anyway. A tincture mixed with 1/4 cup-ish of water or juice is probably just as good as 'straight' (if it's a nasty tasting one, organic grape juice usually kills the taste best). There's a good possibility that straight tincture sublingually (under your tongue) would be absorbed/assimilated the quickest, but I haven't done any research on that.
As far as capsules, they'd probably get digested faster if they were taken on a relatively empty stomach. Last month I ran out of echinacea tincture (forgot to order it...grrr me) and ended up taking some Herb Pharm capsules that I'd had for about a year. I took them on any empty stomach before bed, and I put them in my mouth with a little of water and swished them around for a minute or so...hoping my saliva would 'do it's thing' on the gel caps so I'd be sure not to see any 'echinacea pellets' in the toilet the next day. I took eight capsules, and I think they helped a bit...whatever was giving me the scratchy throat was gone the next morning. But I also took 5,000 mg of Vitamin C to make sure, since I didn't have my usual tincture on hand.