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.