For those describing the Tu154's considerable power/weight ratio, bear in mind this was a Tu154B with the original Kuznetsov engines, rather than the later Tu154M variant, the only one in airline use for the last 15 years or so, with substantially improved Soloviev engines, which much recent documentation refers to.
If we take the inadvertent flap retraction line, there is of course a timelag between selection of retract and the achievement of that, which does vary from airframe to airframe dependent on the state of the hydraulics. When first selected the aircraft would still be accelerating, until the progressive loss of lift overcame the speed.
I can believe the FO still thought they had retracted the gear, and the commander was too absorbed with maintaining flying into unexpected conditions to scan all the controls. I wonder what the FE was doing during this time; are gear and flap indicators repeated on their panel ?