Can you meditate too much as part of a daily routine? Just to follow up from this question - is it possible for an individual to meditate too much? Is there a point when it becomes counterproductive and if so what would the signs be that someone should slacken off their meditation routine?

Just to be clear - I am talking about a meditation routine outside of a retreat setting. The question is about someone's daily meditation routine rather than during a retreat when the conditions and level of support one would receive would be very different.
I'm sure you've heard the phrase "Practice like your hair is one fire"

However, one researcher was looking for people who had so-called "Dark Nights of the soul" experience, i.e. unpleasant experience with meditation. She found that


  "She identified two susceptible demographics: a) men, 18 to 30 years
  old, who go to Asia and do 10 to 20 hrs of meditation/day, and b)
  middle-aged women w/an hr/day practice who go to “say, Spirit Rock
  Meditation Center ... for the last 10 to 20 years”.


ref: http://beyondmeds.com/2014/02/16/dark-night-of-the-soul/

In the case of a lay follower, I don't think we need to go outside of Buddhism to answer the question-- your job will determine the upper bound to how much you can meditate, which I suppose is the whole motivation behind renunciation, to allow more time to meditate. For a lay follower with a day job, fitting in 3 hours a day and maybe more on a weekend (16 maybe?) seems to be the most you can get away with without re-arranging your lifestyle and job to crank up the number of hours.

Anyhow, in my opinion quality trumps quantity, I wish I had a good objective metric for monitoring quality.

Also, in my own practice I've been working on doing more different sorts of meditation, since I already sit on my butt at the office all day staring at a screen (sometimes with concentration, sometimes scatter brained). So I've been trying to mix in prostrations, chants, walking meditation, etc.