(5) Not everybody is more productive when working from home as there may be more distractions at home than at work. Walking the dog, doing the washing up, etc. Troubleshooting certain problems is (far) easier locally than remotely.
Too true. We can work from home occasionally, but my wife hasn't got the idea that working from home is working. It's very nice to be offered cups of tea occasionally, but being asked if you want anything every five minutes - oh and can I come to get something heavy out of the cupboard, empty the bin, see how cute our dog looks as he's gone to sleep leaning in a corner and so on ... I only work from home if I'm snowed in or something as I really do get a lot less done.
When I was working from home a lot, I was in the fortunate position of not having daily deadlines to meet. As a result, I was *more* productive at home. The scheduling freedom meant that I could take care of occasional personal stuff during the day that just couldn't get done on evenings or weekends. But because I tended to be kind of 'uptight Protestant' about my work ethic, (and because I really liked what I was doing), I more than made up for that by working early mornings and late evenings. Being at home also meant that I could take the breaks necessary to understand a problem and/or come up with solutions, without being stressed out about the watchful eyes of co-workers and management seeing me 'slack off'.
IMHO, some weekly presence in the office is required; if not for meetings, group discussions where telepresence isn't enough, etc, then for the social aspect of team building and maintenance. But in a lot of jobs, for a lot of people, two or three days a week working from home can be a win for both employer and employee.