Andy,
Look on the Insulin discussion. I've seen posts there about either Lantus or Levemir having no effect on some people. (It's at Diabetes Management / Medication / Insulin.) You should find some experience like yours to compare notes with.
I think people will say, try Levemir (or if that doesn't work, try old-fashioned stuff like 'human' insulin). It seems to be so individual, what works. But huge doses of anything won't help.
On the Insulin discussion there seem to be lots of people saying they have problems with Lantus.
Good luck - your instinct is quite right, those figures aren't working.
(Though if BMI is high, lo-carb and exercise might help too, if you're insulin-resistant.)