A third-place finish means a two-legged meeting against Queen of the South, with Hamilton Academical lying in wait for the winners. Only then will an SPFL Championship side get to take on the team which finish 11th in the Premiership.
Loy said: "It's the only league in the world I can think of where we have to win three two-leg ties to get promoted. It probably favours the 11th-placed top flight team, who face one two-leg tie. We go into the play-offs with confidence. But all the points we earned mean nothing now and it's like a two-leg cup final against Queen of the South."
Mark Beck had headed Falkirk ahead from a Mark Millar cross only for Kevin Cawley to equalise with a tap-in from Ryan McCord's cut-back.
However, Falkirk stepped up a gear and Scott Shepherd crossed for Craig Sibbald to score before Beck sealed the points with a header after a Will Vaulks cross.
Gary Holt, the Falkirk manager, heaped praise on his team. He said: "We realised by half-time that we were in the play-offs, which are something new for most of our boys but I want them to enjoy the occasion and play with a smile. The team have been great, with our highest points tally, winning so many games and scoring so many goals. I have no regrets as we have played a positive style of football, aiming to entertain and the lads have been magnificent. I warned the players that it's a level playing field now and we are ready for two cup finals against Queen of the South."
Meanwhile, Alloa Athletic were spared the tension of the relegation play-off courtesy of a late Queens goal at Cowdenbeath.
Barry Smith, the Alloa manager, said: "Has this definitely happened, because we were in the dressing room talking about Tuesday's play-off?
"Next thing we heard Queen of the South had scored so it has been a rollercoaster of a day. It's a great achievement for Alloa to stay in the Championship as a part-time club and facing Rangers and Hearts will be a great challenge."