browserify + watchify + viny-transform + multiple bundles

gistfile1.js

// this setup assumes you are using gulp-config for file.src & file.dest
// but can be adapted to vanilla easily.

'use strict';

var transform  = require('vinyl-transform'),
    browserify = require('browserify'),
    watchify   = require('watchify'),

    // consider using gulp-load-plugins

    changed    = require('gulp-changed'),
    gif        = require('gulp-if'),
    rename     = require('gulp-rename'),
    uglify     = require('gulp-uglify'),

    _          = require('lodash'),

    // Task defaults

    defaults = _.defaults({}, watchify.args);

module.exports = function (gulp) {

    var watch   = global.watch,
        options = this.options(defaults),
        file    = this.file,
        cache   = {},
        bundler,
        bundle,

        notify = function (filename) {
            gulp.util.log(gulp.util.colors.green('√') + ' ' + filename);
        };

    bundler = function (options) {

        // leverage vinyl-transform to turn
        // readable stream into vinyl object

        return transform(function(filename) {

            // return previous bundle

            if (cache[filename]) {
                return cache[filename].bundle();
            }

            var b = browserify(filename, options);

            // transforms

            b.transform('debowerify');

            // events

            b.on('bundle', notify.bind(null, 'BUNDLE ' + filename));

            if (watch) {

                b = watchify(b);

                // events

                b.on('update', bundle.bind(null, true));

                // cache for use during watch

                cache[filename] = b;

            }

            return b.bundle();

        });

    };

    bundle = function (check) {

        return gulp.src(file.src)

                    // don't check on first run ( i.e initialisation )
                    // but do for subsequent calls via bundle.on('update')

                   .pipe(gif(check, changed(file.dest, {
                       extension: '.js'
                   })))

                   .pipe(bundler(options))
                   .pipe(gulp.dest(file.dest))

                   // minification

                   .pipe(uglify())
                   .pipe(rename({
                       suffix: '.min'
                    }))
                    .pipe(gulp.dest(file.dest));


    };

    return bundle(!watch);

};

Is this spaced out so that the teacher can write between the lines in red pen?