My employer too is not bad on "cycling." We sponsor a large long distance road cycling event, which staff take part in and always has high uptake (it can actually be difficult to get a place). That however does not translate into high numbers using bikes day-to-day in Edinburgh, myself included... A colleague did the ride a couple of years ago but said herself she wouldn't cycle to work, or in traffic in Edinburgh, because it's too intimidating and dangerous.
I get the feeling our London office is different - there is a secure bike garage which is so busy that you require to have registered your bike to regulate the numbers. There's a bike repair service, plentiful showers, towels available if you're a member of the on-site gym, drying rooms etc. There's also 2 Boris Bike docking stations within 100m of the office which are great when down for a couple of days (colleagues think I'm mad at first, until I leave the hotel 20mins later than them and arrive before...). Further we were one of the (admittedly many) signatories supporting further investment in segregated cycle infra in London.
Now, how does that translate in the regions? I'm not entirely sure to be honest. For our office of c250 people, within a larger office complex there are maybe 10 Sheffield Stands in the secure car park, to be shared amongst us and perhaps 5/6 other companies. There's closer to 60 car parking spaces. We have 4 showers with hairdryers etc which is great and really handy. Nowhere to hang wet towels to dry though.
Thing is, what would it take to get 40% of people willing to cycle? Ultimately - not sure if that's possible. I would estimate that about 60% max of the c250 people are there at any time. The remainder are out and about at clients/meetings/working from home. If I'm going to a client meeting then I generally don't cycle, because I need a clean & ironed shirt!
Things we could do to promote - for one thing actually make people aware of cycling for transport, rather than just as an annual/weekend leisure activity. We have pictures of cycling on the walls but they are all lycra-clad, racing etc. I had to ask around to find where the bike racks are, and they are usually full.
Some sort of voice coming out in support of cycle infra would be helpful - if the large employers of Edinburgh were able to use some sway in the way that they have in London then it could really put some pressure on the council to deliver properly. That would be as big as anything, but would need to be in conjunction with things that make it easier to cycle (drying facilities etc).