Your welcome, here is the science of smoke. Just so you know TBS and Billowing white smoke are exactly the same thing.
The blue you see is the Rayliegh Scattering law. Most common in light dispersed gases. This is the reason the sky is blue.
When the particle and vapor count gets higher the Rayleigh Scatter gives way to the Tyndall scattering. As the particle count increases the scatter of light changes until all wavelengths are being emitted. Hence the white look of the light with more particles. (This is the reason clouds are white)
But the particles remain the same, only the count changes. So to say the white smoke contains "creosote, or something else" is on basis, false, it in fact just contains a large concentration of the same particles that already exist in TBS. It is just the count changing enough so we move from rayleigh scatter to tyndall scatter.
TBS is used by the beginner as a method of controlling smoke is valid, as TBS and looking for it is a true indicator of particle count. The demarkation line between rayleigh and tyndall definately offers a concentration of particle count.
But the thought that white smoke and TBS are an indication of creosote is wrong. Creosote forms from a delta T change in stack temperature verses firebox temperature. Both contain the components to create creosote.
The reason you see many people push the novice to leave the damper open is a simple easy way to keep the novice in control of the firebox by setting up the O2 levels and flow to carry enough heat (infrared energy) from the firebox to the flue without a delta T that creates creosote.
But that method, while effective for the novice operation, wastes fuel and makes tendering the firebox more frequent. As you get more and more experience you will learn to use both the damper and the flue to keep delta T in check and manage the firebox in a more effecient manner.
That skill will allow you to heavy smoke in the beginning of your cooking for a deeper smoke ring. While I understand the want to create an easy rule, when you leave the beginners field and start to run a pit, you will learn to use all levels of smoke.
As I said smoke must be managed, and understanding managing your firebox drafts and flue dampers is an important skill.
Remember if you receive a hard fast rule... it is probably a limitation of the persons knowledge.. the more you do this, the more you find there are guidelines to help you get to the next level, but no hard fast rules.
But I do want to reinforce, that TBS is always a good place to start, and will produce nice results. But eventually you will leave it and learn to lay down the proper particle count to get that bright red ring we so love. Then you will learn to lay them down so you get better and better penetration.