John Sloss, producer of Richard Linklater's much-admired new release Boyhood, has offered cinema patrons who are "not absolutely thrilled" by the film a chance to have the time spent in the cinema "returned" to them.

In a tongue-in-cheek email sent to Sloss' personal mailing list, the veteran producer has offered "any recipient of the email (strictly non-transferable) my patented 'Time Back Guarantee'". Sloss goes on to write: "If you are not absolutely thrilled by Boyhood and/or consider it not to be a good use of your time, I will give you that time back by performing any of your customary chores for up to 2 hours and 43 minutes".

Boyhood was filmed over a 12-year span, following the central character Mason from first grade (aged six) to 12th (aged 18), with the same actor, Ellar Coltrane, performing throughout – along with the rest of the cast, which includes Patricia Arquette, Ethan Hawke and the director's daughter Lorelei Linklater.

Sloss presumably feels on safe ground as reviews for Boyhood have been overwhelmingly positive, and the film currently has a 100% "fresh" rating on the review aggregator Rotten Tomatoes (though this fails to include one notable dissenter, Sunday Times film critic Camilla Long, as the paper has not featured on Rotten Tomatoes since 2009 due to issues with its paywall). However, as a get-out, Sloss suggests "there are scientific methods to determine if you are feigning lack of appreciation".

• Peter Bradshaw's Boyhood review – one of the great films of the decade
• Boyhood: six quibbles with Richard Linklater's masterpiece