I would argue the opposite for a couple of reasons.
#1 – while it is probably pragmatically impossible to show protection below 140/90 because the trial would be cost prohibitive with respect to size, I’m not aware of any data that says that going from 140 to 120-130mmHg is harmful. With diabetes, however, there is data to say that it can be harmful to take people with a long history of poorly controlled diabetes and aggressively treat them pharmacologically to more “normal” levels.

#2 – with the exception of beta blockers and co-morbidities (ie, ACEi for hypertension with renal disease), the “means to the end” don’t seem to matter much to bp. If you lower it through ACE inhibition, an ARB, calcium channel blocker, or a diuretic, it’s more important to get the bp down and the patient to tolerate the drug than it is to worry about which drug it is. With respect to diabetes, though, the end does not seem to justify the means with respect to drugs, at least at our current knowledge (or level of ignorance). Metformin and insulin seem to have some evidence of macrovascular disease protection like heart attacks whereas the TZD class doesn’t. At the end of the day, it seems more important to control bp and LDL cholesterol in diabetics than it is to get A1c down below 7.5% by any means necessary.

Until the medical community starts demanding hard endpoints from the diabetes trials, we’re going to continue to be plagued with drugs in which we are unclear as to their net long term benefits with respect to lessening the burden of microvascular disease (blindness) or macrovascular disease (heart attacks). We’ve focused on treating glucose numbers for too long and ignored the sum total of the disease.