^ plenty! Situations come up. Your case is a good example. (and fine place to plug my units that are portable
lol) As for the need for the screen; the tool of using the screen as a training object is obviously not needed once flowering however, the support and positioning that the screen/trellis/netting provides is also very helpful. Once a plants branches are in a horizontal position they are less capable of bearing the same weight as when they were vertical. The result, is energy spent producing stem structure and "strength" in order to compensate. With the screen, the weight is supported. Without, the weight of flowers causes bending of the branches of which have not been developed in a relative position to bare the force at that angle etc. That bend in turn causes a reaction by the plant to support that weight (ie. energy spent on something other than flowering). Some argue "there is plenty of energy", but thats not the ticket here. The point is to focus energy spend, on flowering production during that set time period in which it occurs. In other words, energy spent producing stem, is time lost producing parts of the plant that become "harvest".
Still however, your own particular set of circumstances and situation most often dictate what will work best. GL
At this point in your observation of trellising cannabis in the manner you have, can you make any determination of how well the design worked and what the pros and cons may have been if you had done anything differently? I believe these questions are important to point out in real experiences like your own, in order to paint the picture black and white for the next guy.