The impossibility of not training

It seems like you are making the best of what you've got which is a very good thing especially if you are pressed for time. If you can get out into the open countryside it is well worth it. Long streches of quiet road are what gave my cycling a new lease of life when I moved out of London and the lanes of Essex were a real relief from traffic when I lived there. If you can get out of Town at all then do it whenever you can, it's proper cycling as opposed to the self preservation required on urban roads. what I took away from Sam's blog was that he was too inclined to pootle along when out riding alone which had served him well when cycling to lose weight but now lacked the required intensity to prepare him for races. It appeared that he'd drawn much the same conclusion himself and decided to find a way of working harder to improve his performance. From what you've written it seems that you're doing your best to maximise the returns from every ride too. I have a good friend who does a short commute through London every day on a Brompton. He treats all the stops for traffic lights as opportunities to do interval sprints and as a result has quads that wouldn't look put of place in a German track team.
I understand your frustrations, your ride is always what you make of it, stick with it and try to explore whenever you can. If you can get put into the Peaks, or anywhere that you can truly appreciate being out on the open roads you won't regret it. Tom Simpson used to ride 25 mles from Harworth to Fox House just to meet up to go training and then have to ride home again. Having ridden the roads he used to train on I can understand why, they are a great combination of beauty and serious challenge. It sounds like you're doing a great job. Good luck with your prepartions for the 2013 season.

HI,Riding for 57yrs this April,riding your bike training is definitely needed,although I use 3 rides a week and have aimed at over 100 miles per week,I still us my rollers for interval training.Obviously now retired I can choose my days,but I do have a day off between rides,where I walk my border collies,as a form of cross training,usually 6 miles wearing my heavy hiking boots.At the end of April our tuesday evening 10 ML TT,s start,and they are great for gaining speed.During the bad icy weather it was rollers mostly,on better winter days I either ride gears,but my favourite way of building endurance,is to ride my fixed wheel Langdale,on 72 inch fixed wheel,most of us old timers cut our cycling teeth on Fixed,it is smooth pedalling and a great way of keeping warm when Idle winds abound.Please dont get too wound up by those who munch big miles,some do others tell Porkies!!FOXY

Riding your bike IS training. End of story. It is specific to whatever speed/power/cadence you are pushing at that specific moment in time. Is it "useful training" is another question.

Ride a smaller loop more times. Thats what i do i don't have time for a big ride, but need to train.