Is it considered safe to connect ground to neutral with GFCI outlets?
Yes you can replace two prong ungrounded receptacles with GFCIs. Since you say you are a retired electrician I'll be brief. 2014 NEC Article 406.4(D)(2) will explain how to do it.

No you should never bootleg a ground. If you want to install a ground, it can be added as outlined in 2014 NEC Article 250.130(C) and Exhibit 250.47. They can guide you through it.

I am mentioning the NEC year because these articles have moved around in different editions. Good luck explaining it to contractors. Hope this helps.