Harrison revealed in his Yahoo! TV blog that a scene in which he sat down and chatted with Viall wasn't shown in last week's episode.
"We talked about how serious his feelings were becoming," Harrison wrote.
During his one-on-one date with the 31-year-old Dallas attorney in New Orleans, Viall appeared to develop strong feelings for Lindsay.
"It had been quite some time since Rachel, who got the First Impression Rose, had any serious quality time with Nick. It was Nick's first time in New Orleans, and there was no better tour guide for him than Rachel," Harrison said, referencing the fact Lindsay had traveled to New Orleans shortly before her The Bachelor adventure for a funeral.
"Even though Nick took the lead on the date, Rachel really helped him relax and have a good time."
Harrison noted that Lindsay was the perfect choice for the date in which the couple walked through a marketplace and soaked in local culture.
"In this very pressure-filled week, Rachel was exactly what he needed to keep his journey to falling in love on course," Harrison wrote in his blog. "A concert by Lolo at Preservation Hall and a second line in the French Quarter really got this week started right."
Lindsay allowed herself to be vulnerable on the date, and her honesty prompted Viall to open up as well. The Bachelor wanted Lindsay to feel confident in their relationship, so he gave her some major reassurance.
"The chemistry between the two of them is undeniable," Harrison explained.
"And Nick let Rachel know that he feels like she is going to be in his life for a very long time. I hope those promises don't come back to haunt him."