I find myself in strong disagreement with the editorial.
A) shouldn't be allowed near a computer without at least 3 armed guards to make sure they don't touch anything
every error correction mechanism known to man
C) Need a dedicated team of error correction specialists to fix all the entry mistakes made by said sales people.
Lacking that (sigh) you must have strong editing controls at the front end to catch at least some of the bone-headed and (frankly) lazy mistakes and deliberate lack of data entry most sales people consider adequate.
Been there, done that, ate the tee-shirt from sheer frustration bordering on genocidal rage... (sales people are a seperate species, right? :hehe
Seriously though, the best time to correct any error is when it's made. Spell checking is the least of your problems when the sales force is allowed to enter data (shudder). Even having a DMZ and über-strong error checking won't help all that much because rejecting a record for data errors--even if you can find them (and most data errors aren't correctable since the data is either missing entirely or not verifiable without access to the actual paper records) isn't much less frustrating for the sales force than error messages at the front end.