3/16 on flat or nearly flat ground will not work well unless you have mechanical vacuum on it. Even then, line friction will reduce the flow.
That being said, I may be one of the very few (if not the only one) who do just that. I have runs of 3/16 pulling as much as 4-500' from trees that are nearly at the same elevation, and I have several runs that actually pull from lines a few feet below the main lines. I only have 2 mainlines, both are 1" and I then have 2 sap ladders on each. While my results are good, I'm sure it could do better if I wasn't fighting the wisdom of the experts. This past year I got .49 gal/tap in syrup, the year before I got .52 GPT. Before that I had never used the 3/16 except as designed.
I run 26-27" mechanical vacuum using an antique pump, an old BB4 piston pump.
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.