Vautier and Allmendinger were joined at Texas by 21-year-old Firestone Indy Lights racer Carlos Munoz, who has been handed a seat to attempt the Indy 500 by Andretti Autosports.
More experienced hands taking the opportunity to test at Texas - which hosts the eighth round of the 19-race 2013 IndyCar season on June 8 - included Vautier's team mate and compatriot Simon Pagenaud, team owner-driver Ed Carpenter, AJ Foyt's Takuma Sato, and Rahal Letterman Lanigan duo Graham Rahal and James Jakes.
Having more cars on track was a help for the rookies, explained Vautier, especially preparing for the actual Firestone 550 race that he will be competing in two weeks after the Indy 500.
"The challenge coming back here will be all the things you have to do with other people on the track," he said. "The car can react differently from lap to lap by the way it moves around, so that was helpful in general.
"There's lots of grip and you can really feel the compression in the corners, and with the wind it was pretty tricky," he added. "It might be even trickier in June when we come back because it will be significantly warmer."
While Vautier will definitely be competing here in June, Munoz is unlikely to; and the jury is still out on whether Allmendinger will be tempted to stay for a longer stint back in open wheel racing or whether he'll go back to focussing on NASCAR after participating in the greatest spectacle in motorsport.
The formal Rookie Orientation Program itself will be held on April 11 at Indianapolis Motor Speedway, which is a 2.5-mile circuit unique in motor racing and very different in characteristics from the high-banked 1.5-mile Texas circuit.
All drivers who have not recently competed in the Indy 500 must successfully complete ROP before being allowed to participate in qualifying, in which only the top 33 cars make it into the actual 97th running of the Indianapolis 500 on May 26.