As this is a beginners section I'll expand ( no pun intended)
although this should be fine with lower profile tyres and good fitting technique.
This is assuming normal, not tubeless.
When you put the new/repaired tub in, start the tyre at the valve the put the valve area on the ground and apply pressure with your foot pushing the rim toward the ground. This keeps the bead out of its groove in the I'm until re-fitting is complete.
Before inflating, push he valve stem back into the tyre so that the thick part of the tube at the base of the valve goes inside the tyre rather than topping the tyre from seating correctly.
Then pull the valve out a bit and if threaded, apply the ring-nut.
The tyre bead should sit nicely into the rim and te often found indicator line will align all the way round the tyre ON BOTH SIDES.
(if you ave one and the time, a couple of pumps with your backup mini pump will fill out the tyre)
You should be safe to inflate using Co2 now
On the question, does it make a difference?
Last year out on a very hilly 2-day 170 miler, I got a thorn flat 10 mile in.
Trying to save cartridges, I took the tyre up with a mini-pump and 5 mile on got a snakebite flat.
Another new tube and the Co2 sharp fixed that.