It is kind of shocking to hear you say this. Certainly you should only undertake dilution under your doctors guidance, but it isn't a misuse. Dilution is right there on the prescribing information, an appropriate and supported practice from the manufacturer. They sell you the stuff to do it. The steps to do this are straightforward and sterile.
Here is what the prescribing information for Humalog says:
16.3 Preparation and Handling
Diluted HUMALOG U-100 for Subcutaneous Injection — HUMALOG may be diluted with Sterile Diluent for HUMALOG for subcutaneous injection. Diluting one part HUMALOG to nine parts diluent will yield a concentration one-tenth that of HUMALOG (equivalent to U-10). Diluting one part HUMALOG to one part diluent will yield a concentration one-half that of HUMALOG (equivalent to U-50)
And I don't understand your concerns about contamination. You use a syringe and vials of insulin and sterile diluent. If you don't trust these devices you shouldn't trust a regular syringe and vial or a pen or even a pump. These delivery and dilution methods have been designed and tested to maintain sterility, I'm sorry you don't trust them.
So if you don't feel comfortable with diluting insulin yourself you can ask you pharmacist to do this or even take it a step further and order diluted insulin from a compounding pharmacist whose job is "exactly" that, to mix custom medications per doctors orders. If you hung out over ChildrenwithDiabetes you would see that dilution is a not uncommon practice. I understand you don't like Bernstein, but your comments are not supported by the manufacturers nor others in the diabetes and health communities.