I too had been advised of all the combing when I started considering line sources, but physics aside, my ears tell me something else.
I had a chance to hear a used pair of Scaena 3.2's today that were for sale. I have heard the 3.2 in various versions and systems over the past 2.5 years, so I am familiar with how it performs. In this particular demo, it was not setup anywhere close to ideally, since the speakers had just come into the dealer the day before, and there was alot of other gear around. However they didn't have a problem with me tweaking the placement and crossover levels, so I was able to coax a reasonable performance from them, even though no attempt had yet been made to pair them with best match of cables and amps in the store.
That being said, it was the best demo I have ever heard in that store by a significant margin, and that has included Magico V3's, Rockport Mira's various wilsons, Martin Logan CLX, etc. Now to be fair, none of those demos were what I'd consider proper set ups either, but I believe one can tell the basic character of a speaker, even in marginal setups such as these.
I'm not saying the Scaena is the typical line array, in that its almost baffleless design is rather cutting edge, but to my ear it what no other speaker in that showroom had ever done, and made me think that this was a product I could own for a long time. The level of detail, purity, and imaging achieved a level of realism that put them over the top for me. Plus the ability to listen from mid field and far field I thought was fantastic since they drop half of what point sources do over distance. And I didn't feel that instrument size was being overblown.
As I mentioned I am getting in some line sources to audition soon, where the drivers are positioned even closer together than the Scaena. I believe that this actually helps with combing, the closer the drivers are to each other.