addresses "with only 99.9 there will be noticeable white gap in bars"

Should update the comment here too. I believe with only 99.9 there will be small but noticeable white gap on the progress bars in some cases.
remove redundant nil-check (learner.report_learner is non-nil)

from comment:
learner.report_learner is supposed to always be non-nil, checkout out learner.rb:42