From the Grayson FAA GC Letter of Interpretation
"Section 61.65(d)(2) states,in relevant part, that a person applying for an instrument-airplane rating must have logged forty hours of actual or simulated INSTRUMENT TIME, of which fifteen hours must have been received from an authorized instructor who holds an instrument-airplane rating. Section 61.195(c) states, in relevant part, that a flight instructor who provides INSTRUMENT TRAINING for the issuance of an instrument rating must hold an instrument rating on his or her pilot certificate and flight instructor certificate that is appropriate to the category and class of aircraft used for the training provided." Note the difference between INSTRUMENT TIME and INSTRUMENT TRAINING. Also note that the regulation states "a flight instructor who provides INSTRUMENT TRAINING for the issuance of an instrument rating must hold an instrument rating on his or her pilot certificate and flight instructor certificate that is appropriate to the category and class of aircraft used for the training provided," and makes no distinction as to level of pilot certificate - commercial or ATP - required. Further, 61.65(d)(2)(i) and (ii) requirements must be with a CFII and 61.65(i) states "Use of an aviation training device. A maximum of 10 hours of INSTRUMENT TIME [NOT INSTRUMENT TRAINING] received in a basic aviation training device or a maximum of 20 hours of INSTRUMENT TIME received in an advanced aviation training device may be credited for the INSTRUMENT TIME requirements of this section if— (1) The device is approved and authorized by the FAA; (2) An authorized instructor provides the INSTRUMENT TIME [NOT INSTRUMENT TRAINING] in the device; and (3) The FAA approved the instrument training and instrument tasks performed in the device.
In the GC letter to Rohlfing (2016), the GC states: "Under§ 61.65(d)(2), "the required instrument time other than instrument training does not require the presence of a CFI but only the presence of an individual qualified to act as a safety pilot or as a pilot in command of an operation in actual instrument conditions." For the simulator, 61.51 Pilot logbook, (g) Logging instrument time, 61.51(g)(4) A person can use time in a flight simulator, flight training device, or aviation training device for acquiring instrument aeronautical experience for a pilot certificate, rating, or instrument recency experience, provided an authorized instructor is present to observe that time and signs the person's logbook or training record to verify the time and the content of the training session." For other than the 15 INSTRUMENT TRAINING hours required to be obtained with a CFII, a CFI can assist the pilot i obtaining the other 25 hours, but may not logged the hours as INSTRUMENT TRAINING - may only log INSTRUMENT TIME.