Improve inference in several places

[timholy]

This disabling of the debugging statements may be a bit unfortunate,
but we haven't needed them lately and they are easy to uncomment.

xref timholy/CodeTracking.jl#73

[codecov]

Codecov Report

Merging #438 (c37c168) into master (8bd596b) will increase coverage by 0.45%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #438      +/-   ##
==========================================
+ Coverage   88.91%   89.37%   +0.45%     
==========================================
  Files          12       12              
  Lines        2274     2268       -6     
==========================================
+ Hits         2022     2027       +5     
+ Misses        252      241      -11     

Impacted Files	Coverage Δ
src/interpret.jl	86.65% <ø> (+0.76%)	⬆️
src/breakpoints.jl	95.02% <100.00%> (ø)
src/construct.jl	90.76% <100.00%> (ø)
src/utils.jl	89.41% <100.00%> (+1.88%)	⬆️
src/optimize.jl	97.90% <0.00%> (-0.01%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 8bd596b...e058b3b. Read the comment docs.