My understanding is that you want full combustion i.e a flame because that is what produces the gases and nitric oxide that you associate with high end barbecue. Soaking produces a lot of heavy visible smoke, but it's a lot of soot and carcinogenic compounds that aren't as desirable. The nitric oxide from full combustion is what produces the smoke ring, which is why electric smokers cant actually produce a smoke ring since they don't cause the wood to fully combust, only pyrolysis.

If you look at any of the famous bbq places like Franklin's or Pecan Lodge in Texas, they don't soak their wood and they smoke with full raging fires rather than a smoldering burn.