To get an idea of the cost of tiling (with bspwm, quarter screen tile and 2560x1440@60Hz screen):

  hyperfine -L args '','-c floating' 'st {args} -e true'
  Benchmark 1: st  -e true
    Time (mean ± σ):      25.0 ms ±   2.7 ms    [User: 10.5 ms, System: 3.7 ms]
    Range (min … max):    14.8 ms …  44.1 ms    197 runs

  Benchmark 2: st -c floating -e true
    Time (mean ± σ):      22.7 ms ±   2.6 ms    [User: 10.3 ms, System: 3.9 ms]
    Range (min … max):    20.7 ms …  35.4 ms    123 runs

  Summary
    'st -c floating -e true' ran
      1.10 ± 0.17 times faster than 'st  -e true'

Flexing my system too, heh.