I think the general answer to this one is probably "swami"
swami... again
I could give a whole list of quotes.
Now- something I see all to often is someone asking quite silly questions- people wanting to know impromptu ways to fly, how to vanish without any covers, how to read minds e.t.c. Whilst impractical and often very ill thought out, the idealists (who more often than not know very little about magic) have something called 'vision'. They know how magic is supposed to look and aiming for that vision is the way 'magical' magic is created. Here we have an example- a spectator thinks of anything and thier thought is divined straight out of their head. No 'compromise'- it is something many people new to mentalism expect. But there isn't actually anything wrong with that thinking- there is a lot of very strong mentalism created with that vision in mind. And true, if you were a real mind reader, you wouldn't need billets, you wouldn't need to reveal your prediction afterwards and that is a vision which can result in some very powerful mentalism. Personally, I strive to achieve that aesthetic- and find myself using a lot of dual reality and linguistic deceptions, cold reading, hellstromism, hypnosis and dare I mention some nlp, psychological subtleties (You'll have to get banachek's and Tomo's book(s) about that) non-verbal communication and various other techniques. As a result, I am approaching that aesthetic.
BUT. and I mean:
BBBBBBBBBBBBBUUUUUUUUUUUUUUUUUUUUUUUUUTTTTTTTTTTTTTTT,
Billets are only a problem if YOU think they are. And as has been said 5 gazillion times already it is all about performance. If you create the situation where is feels natural that the spectator names their thought first to allow you to 'swami' then it doesn't register with the audience. I mentioned som subtleties with the swami gimmick earlier. Same with the Billet work, it is a HUGE aspect of mentalism and if you view it as compromising on what a real mind reader would do, the audience will pick up on that. I can tell you, a real mind reader think twice about weather writing their thoughts down would compromise thier ability and I know that people never question writing thier thought if the enviroment is right, and as Corinda said treat it with indifference. I have seen mentalists who give the spectator the billet and get them to write the thought without any justification and the audience senses that that is important some way because the performer valued the billet, but if it is played down I PROMISE you, with the right performance nobody will even remember the billet. So, in the spectator's mind you are achieving that aesthetic I spoke about earlier. And that is the central theme of magic- it is not about how clever the method is but how strong the effect is or rather what the spectator is experiencing- if they feel satisfied that the billet is not important, you cannot see what they have written then you have read their mind. It is all about how the audience percieves it and that all comes down to your presentation. I don't want to knock your vision of 'pure' mentalism, because that can ONLY be a good thing, but.. I mean, come on, your on a magic forum telling us you'd rather not use billets or the swami gimmick. They are you most trust worthy devises. I did a whole impromptu routine with billets on one mate and that was the first time I had read his mind. I treated them with indifference and believed in my imaginary abilities. From that point that was the only thing he had seen me do, and the next time he saw me perform I was doing a trick which I was mighty thrilled with- the method was very elegant and difficult and the effect was that of 'pure' mind reading, nothing was written and the spectator selection was fair and I revealed my predictions first. I was chuffed and indeed it was a strong effect. I looked at my mate who had watched me perform for the second time and I looked at him with anticipation and said, 'so?' to which he replied 'Yeah, I already know you can read minds, I think that thing you did with me was better.' I was slightly temporarily crushed and upon composing myself realised it was a positive thing.So the moral of the story- aim to make your audience believe in your ability and by all means keep aiming for that pure vision
of what mentalism should look like- but don't give up billets, don't give up the swami- you are chucking away your most versatile and potent tools.
''To go wrong in one's own way is better than to go right in another's.'' Dostoevsky's Razumihin.