But even then, would you allow him to go into your bedroom and watch you have sex?
Well, some would, it seems.
And pay good money for it too.
Their hope: That he can help them save their crumbling marriage.
Several local couples in their late 30s and 40s have engaged homegrown sex guru Wei Siang Yu to do so.
Dr Wei (L), popularly known as Dr Love, says he has sat in the same room with eight couples in the past two years while they had sex.
They pay 'a couple of thousands' for five or so sessions which could stretch over three months.
One of these sessions includes Dr Wei visiting their homes, where the couples give him a 'live demo' so that he can correct their mistakes and pinpoint their problems.
Dr Wei, who attended medical school at Melbourne's Monash University, gets many requests from couples who don't think three's a crowd - some even from Malaysia and Indonesia. But he has to turn them down because of his busy schedule.
And he said he can sift out genuine couples in need of help from those who simply want to indulge their kinky fantasies.
DESPERATE
Still, his methods are unusual and can raise eyebrows.
Dr Wei, 38, who is also chief editor of the Love Airways sex magazine, and has his own radio and TV show, spoke to The New Paper on Sunday from his Playroom sex-counselling centre on Seah Street.
'I must make sure it's a case that's really super desperate and there's nobody else who's able to help them,' he said. 'Only then will I do it.'
But is it necessary and ethical for a doctor to do this? Doesn't it smack of voyeurism?
Dr Wei countered cautiously: 'Yes, it's a very difficult and sensitive issue.
'That's why I deal with only those whom I know have very serious, real problems - to the point where they keep begging you so many times and actually drop tears (over their sex lives).'
The couples were all on the brink of divorce because of years of bad sex - 'no ejaculation, no orgasm, no feeling, no communication'.
They were either not keen to try, or had already given up on, the 'normal medical system' - seeing GPs, counsellors, urologists and gynaecologists.
Still, he is aware of the potential problems - which was evident by his reaction when we asked him for an interview for this article. He was initially reluctant, as he was concerned it may give his detractors an excuse to accuse him of 'encouraging couples to be naked in front of doctors'.
But he insisted that he's only trying to help his patients, for most of whom, it's their 'last resort'.
The president of the Singapore Medical Association, DrWong Chiang Yin, said that although Dr Wei's methods 'sound unusual', it's 'not fair' for the organisation to comment as its committee members aren't 'experts' in the area of sexual health.
Dr Wong said: 'If he claims his patients gave consent, then it may not violate the ethical code.'
The Singapore Medical Council declined to comment as it usually doesn't look into practices of individual doctors unless a complaint has been lodged.
However, a veteran gynaecologist, Dr Atputharajah Vytialingam, who has counselled hundreds of couples with sexual problems, feels there is 'no necessity' to watch them have sex.
He said: 'I'm surprised because even sex clinics in the US don't do such things - unless it's for research purposes. It's definitely not part of accepted practice.
'Even if a doctor gets the patient's consent, he is in a position of trust and power, so there's always possibility of abuse - especially if the patients are so desperate that they'll do things they won't normally do.
'So he has to figure out how far he can go and set his own boundaries.'
But what do the couples themselves say?
When we asked to speak to them, Dr Wei said they have completed their sessions and are 'not media-friendly'.
However, he said they need not be self-conscious or conservative when they do the deed with him around.
'The majority were really relaxed, enthusiastic and open (in showing me their problems). Maybe because they think I'm a friendly, non-judgmental doctor and they are comfortable with me. They take me almost like a mirror to give them feedback.'
Usually, one sex session is enough for Dr Wei to 'get the picture'.
He admits that watching couples having sex 'isn't the most comfortable position to be in', and he does it 'almost like a scientist'.
'I take an objective, professional approach. I'm there solving problems, looking at the faces, expressions, movements and body parts.'
With one couple, he managed to diagnose that the woman suffered from hypothyroidism, which caused her to feel cold all the time and unable to have sex.
He recalled: 'Actually, she doesn't want to be naked, but she doesn't know (about her condition). And the aircon made their bedroom even colder than winter!'
In another case, he identified genital warts around the woman's vagina, and proceeded to give the couple a tutorial about sexually-transmitted diseases.
And because jet-setting Dr Wei is in Singapore for only two or three days every week and doesn't have time to follow up on the cases, he has a team of local doctors who take over.
UNUSUAL
He has found cases of childhood sexual abuse, androgen problems and vaginismus or menopause and has referred them to psychiatrists, urologists or gynaecologists.
'My role is to create a multi-disciplinary, evidence-based approach for couples,' he said. 'I'm able to use my experience, and their openness to communicate with me, to understand the case from inside out.'
Dr Wei may be unusual in adopting such an approach, but he is not the only one getting such requests.
Even non-medical sex therapists aren't spared.
Tantra coach and founder of Tantrapath Christina Low, 36, said that in the last three months, about 10 couples have tried to make appointments with her via e-mail or phone, asking her to meet them at a hotel and teach them tantric sex.
She said: 'They think if a teacher is around, she can bring them to a higher level - whether it is different techniques or positions - and they can have better sex.'
She always says no to such requests.
'I find it very strange, and it's not necessary,' she said.
'I want my clients to eventually be the witness to their own lovemaking, that they become so good that they don't need any teacher.'
During her private sessions, couples are clothed.
Even when the men are taught how to find their partner's G-spot.
The women then remove their underwear but are covered by a sheet.
American Bill M has been attending Ms Low's classes with his Singaporean girlfriend for two months, and believes their sex lives can be improved without any 'show-and-tell'.
The 43-year-old finance manager enjoys tantric exercises because they are 'sensual yet wholesome', but doesn't want sex to become 'artificial, exhibitionistic and no longer sacred'.
Another couple who took Ms Low's coaching is MrDec K and his wife, who have a 3-year-old daughter.
The 36-year-old manager said they went through 'a rough patch' which caused them to find sex 'discomforting', and are currently trying to 'reignite the flame'.
They have gone for counselling and consulted a gynaecologist for their problems, but the marriage hasn't deteriorated to the point where drastic measures need to be taken.
He said: 'It's a bit extreme, but to each his own. It doesn't fit what I expect or can accept, but if it's done in a professional manner, I don't see anything wrong with it.'
